Filed Pursuant to Rule 424(b)(5)
Registration No. 333-277309

PROSPECTUS SUPPLEMENT

(To prospectus dated February 23, 2024)

IDEX CORPORATION

$500,000,000 4.950% Senior Notes due 2029

We are offering $500,000,000 aggregate principal amount of our 4.950% Senior Notes due 2029 (the “notes”). We will pay interest on the notes semi-annually in arrears on and of each year, commencing March 1, 2025. The notes will mature on September 1, 2029.

Prior to August 1, 2029 (one month prior to the maturity date of the notes) (the “Par Call Date”), we may redeem the notes at our option, in whole or in part, at any time and from time to time, at the redemption price described in this prospectus supplement under the caption “Description of the Notes—Optional Redemption.” On or after the Par Call Date, we may redeem the notes, in whole or in part, at any time and from time to time, at a redemption price equal to 100% of the principal amount of the notes being redeemed, plus accrued and unpaid interest thereon to, but excluding, the redemption date. See “Description of the Notes—Optional Redemption.” If we experience a change in control triggering event as described in this prospectus supplement, we may be required to offer to purchase from holders all or part of their notes at a purchase price equal to 101% of the principal amount of the notes, plus accrued and unpaid interest, if any. See “Description of the Notes—Change of Control Offer.”

We intend to use the net proceeds from this offering, together with available revolving credit facility borrowings and cash on hand, to (i) fund the cash consideration payable by us for the Mott Acquisition (as defined below) (“Mott”) and (ii) pay fees and expenses in respect of the foregoing. This offering is not conditioned upon the consummation of the Mott Acquisition, which, if completed, will occur subsequent to the closing of this offering. We cannot assure you that the Mott Acquisition will be consummated on a timely basis, on the terms described herein, or at all. See “Summary—Recent Development—The Mott Acquisition” and “Use of Proceeds.”

If (i) the Mott Acquisition is not consummated on or before the later of (x) November 20, 2024 or (y) such later date to which the outside date under the Mott Acquisition Agreement (as defined below) as in effect on the closing date of this offering may be extended in accordance with the terms thereof, any such extension to be set forth in an Officer’s Certificate (as defined below) delivered to the trustee (as defined below) prior to the close of business on November 20, 2024 (the later of (x) and (y) being referred to herein as the “Special Mandatory Redemption End Date”), (ii) prior to the Special Mandatory Redemption End Date, the Mott Acquisition Agreement is terminated according to its terms without the closing of the Mott Acquisition or (iii) we otherwise notify the trustee in writing that we will not pursue the consummation of the Mott Acquisition (any event in clause (i), (ii) or (iii), a “Special Mandatory Redemption Event”), then we will be required to redeem the notes at a special mandatory redemption price equal to 101% of the aggregate principal amount of the notes, plus accrued and unpaid interest, if any, to, but excluding, the Special Mandatory Redemption Date (as defined below) (subject to the right of holders of the notes of record on the relevant record date to receive interest due on an interest payment date falling prior to the Special Mandatory Redemption Date) (such redemption, a “Special Mandatory Redemption”). The net proceeds from this offering will not be deposited into an escrow account pending completion of the Mott Acquisition or any Special Mandatory Redemption, nor will we be required to grant any security interest or other lien on those proceeds to secure any redemption of the notes. See “Description of the Notes—Special Mandatory Redemption.”

The notes will be our unsecured senior obligations and will rank equal in right of payment to all of our existing and future senior indebtedness.

We do not intend to apply for listing of the notes on any securities exchange or for inclusion of the notes in any automated dealer quotation system. Currently, there is no public market for the notes.

Investing in the notes involves risks. See “Risk Factors” on page S-9 of this prospectus supplement and “Risk Factors” contained in our Annual Report on Form 10-K for the year ended December 31, 2023, which is incorporated by reference herein, to read about certain risks you should consider before investing in the notes.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The underwriters expect to deliver the notes only in book-entry form through the facilities of The Depository Trust Company for the accounts of its participants, including Euroclear Bank SA/ NV, as operator of the Euroclear System, and Clearstream Banking S.A., on or about August 21, 2024, which is the tenth business day following the date hereof.

Joint Book-Running Managers

Senior Co-Managers

Co-Managers

The date of this prospectus supplement is August 7, 2024.

TABLE OF CONTENTS

Prospectus Supplement

Prospectus

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ABOUT THIS PROSPECTUS SUPPLEMENT

We provide information to you about this offering in two separate documents. The accompanying prospectus provides general information about us and securities we may offer from time to time, some of which may not apply to this offering. This prospectus supplement describes the specific details regarding this offering. Generally, when we refer to the “prospectus,” we are referring to both documents combined. Additional information is incorporated by reference in this prospectus supplement and the accompanying prospectus. To the extent there is a conflict between the information contained in this prospectus supplement, on the one hand, and the information contained in the accompanying prospectus or any document that has previously been filed and is incorporated into this prospectus by reference, on the other hand, the information in this prospectus supplement shall control.

You should read this prospectus supplement, the accompanying prospectus, the documents incorporated by reference into this prospectus supplement and the accompanying prospectus and the additional information described under “Where You Can Find More Information” and “Information Incorporated by Reference” in this prospectus supplement before deciding whether to invest in the notes offered by this prospectus supplement.

We are responsible for the information contained and incorporated by reference in this prospectus supplement, the accompanying prospectus and in any related free writing prospectus we prepare or authorize. We have not, and the underwriters have not, authorized anyone to give you any other information, and neither we nor the underwriters take responsibility for any other information that others may give you. If you are in a jurisdiction where offers to sell, or solicitations of offers to purchase, the notes offered by this document are unlawful, or if you are a person to whom it is unlawful to direct these types of activities, then the offer presented in this document does not extend to you. You should assume that the information contained and incorporated by reference in this prospectus supplement, the accompanying prospectus and any free writing prospectus with respect to this offering filed by us with the Securities and Exchange Commission (the “SEC”) is only accurate as of the respective dates of such documents. Our business, financial condition, results of operations and prospects may have changed since those dates.

Unless we have indicated otherwise, or the context otherwise requires, references in this prospectus supplement and the accompanying prospectus supplement to the terms “we,” “us,” “our,” “the Company” or “IDEX” or other similar terms mean IDEX Corporation and its direct and indirect subsidiaries on a consolidated basis.

You should not consider any information in this prospectus supplement or the accompanying prospectus to be investment, legal or tax advice. You should consult your own counsel, accountants and other advisers for legal, tax, business, financial and related advice regarding the purchase of any of the notes offered by this prospectus supplement.

WHERE YOU CAN FIND MORE INFORMATION

We are subject to the information reporting requirements of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and, in accordance with these requirements, we are required to file periodic reports and other information with the SEC. This prospectus supplement is part of a registration statement that we filed with the SEC. The registration statement, including the attached exhibits, contains additional relevant information about us. The rules of the SEC allow us to omit from this prospectus supplement and the accompanying prospectus some of the information included in the registration statement. You will find additional information about us in the registration statement and the exhibits and schedules filed therewith and in our reports and other information incorporated by reference herein. The SEC filings are available at the website maintained by the SEC at http://www.sec.gov.

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INFORMATION INCORPORATED BY REFERENCE

The SEC allows us to “incorporate by reference” the information contained in documents we file with the SEC, which means that we can disclose important information to you by referring to those documents. The information incorporated by reference is an important part of this prospectus supplement. Any statement contained in a document which is incorporated by reference into this prospectus supplement is automatically updated and superseded if information contained in this prospectus supplement, or information that we later file with the SEC, modifies or revises that statement. Any such statement so modified or revised shall not be deemed, except as so modified or revised, to constitute a part of this prospectus supplement. We incorporate by reference the following documents we filed, excluding any information contained therein or attached as an exhibit thereto which has been furnished, but not filed, with the SEC:

Any documents we file pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this prospectus supplement and prior to the termination of the offering of the notes to which this prospectus supplement relates will automatically be deemed to be incorporated by reference into this prospectus supplement and be deemed a part of this prospectus supplement from the date of filing such documents, except to the extent any information contained in or attached to such documents has been furnished, but not filed, with the SEC.

The documents incorporated by reference into this prospectus supplement are available from us at no cost upon your request. We will provide a copy of any and all of the information that is incorporated by reference into this prospectus supplement to any person, without charge, upon written or oral request. If exhibits to the documents incorporated by reference into this prospectus supplement are not themselves specifically incorporated by reference into this prospectus supplement, then the exhibits will not be provided.

Requests for documents relating to us should be directed to:

Abhishek Khandelwal

Senior Vice President and Chief Financial Officer

IDEX Corporation

3100 Sanders Road

Suite 301

Northbrook, Illinois 60062

(847) 498-7070

We also maintain a website that is located at www.idexcorp.com. Information on or accessible through our website is not part of, or incorporated by reference into, this prospectus supplement.

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FORWARD-LOOKING STATEMENTS

This prospectus supplement, the accompanying prospectus (including the information incorporated by reference in this prospectus supplement and the accompanying prospectus) and any free writing prospectus with respect to this offering filed by us with the SEC contain “forward-looking” statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended. These statements may relate to, among other things, the expected benefits of the Mott acquisition, the expected impact of the acquisition on our product offerings or proposed product offerings, our combined existing and new customers and access to high-value end markets, the enhancement of our business strategy, integration plans, the expected growth opportunities, profitability and synergies resulting from the acquisition, including the timing of such expected synergies, the present value of expected tax benefits, the anticipated long-term value to our shareholders, and the expected timing for the closing of the transaction, our business strategy, outlook and the assumptions underlying these expectations, plant and equipment capacity for future growth, planned production, anticipated future acquisition behavior and capital deployment, inventory recalibration and future order stabilization and lead time, expectations regarding market sector contraction, recovery, stabilization or growth, availability and sufficiency of cash and financing alternatives, the anticipated benefits of our recent acquisitions and the expected timing for the closing of the Mott Corporation acquisition, and are indicated by words or phrases such as “anticipates,” “estimates,” “plans,” “guidance,” “expects,” “projects,” “forecasts,” “should,” “could,” “will,” “management believes,” “the Company believes,” “the Company intends,” and similar words or phrases. These statements are subject to inherent uncertainties and risks that could cause actual results to differ materially from those anticipated at the date of this prospectus supplement. The risks and uncertainties include, but are not limited to, the following: levels of industrial activity and economic conditions in the U.S. and other countries around the world, including uncertainties in the financial markets; pricing pressures, including inflation and rising interest rates, and other competitive factors and levels of capital spending in certain industries; the impact of catastrophic weather events, natural disasters and public health threats; economic and political consequences resulting from terrorist attacks and wars; our ability to integrate Mott and to acquire, integrate and operate acquired businesses on a profitable basis; cybersecurity incidents; the relationship of the U.S. dollar to other currencies and its impact on pricing and cost competitiveness; political and economic conditions in foreign countries in which we operate; developments with respect to trade policy and tariffs; interest rates; capacity utilization and the effect this has on costs; labor markets; supply chain conditions; market conditions and material costs; risks related to environmental, social and corporate governance issues, including those related to climate change and sustainability; and developments with respect to contingencies, such as litigation and environmental matters and the other risk factors identified under the heading “Risk Factors” in this prospectus supplement and under the heading “Risk Factors” in our Annual Report on Form 10-K for the fiscal year ended December 31, 2023 and the other reports that we file with the SEC, each of which is incorporated by reference herein. Additional factors that may cause risks and uncertainties include those discussed in the sections entitled “Business” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” in our Annual Report on Form 10-K for the fiscal year ended December 31, 2023 and in our Quarterly Reports on Form 10-Q for the fiscal quarter ended March 31, 2024 and June 30, 2024 and the risk factors and other information discussed in other documents that are incorporated or deemed to be incorporated by reference in this prospectus supplement and the accompanying prospectus. The forward-looking statements included in this prospectus supplement, the accompanying prospectus, any document incorporated by reference herein or therein or any free writing prospectus are only made as of the date on which it is made, and management undertakes no obligation to publicly update them to reflect subsequent events or circumstances, except as may be required by law. Investors are cautioned not to rely unduly on forward-looking statements when evaluating the information presented here.

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RISK FACTORS

Investing in the notes involves risk. Prior to making a decision about investing in our securities, and in consultation with your own financial and legal advisors, you should carefully consider the following risk factors, as well as the risk factors incorporated by reference in this prospectus supplement from our Annual Report on Form 10-K for the year ended December 31, 2023 under the heading “Risk Factors” and other filings we may make from time to time with the SEC. You should also refer to the other information in this prospectus supplement and the accompanying prospectus, including our financial statements and the related notes incorporated by reference into this prospectus supplement.

Risks Related to the Notes

The notes will not be guaranteed by any of our subsidiaries and will be effectively subordinated to the indebtedness and other liabilities of our subsidiaries.

The notes are our obligations exclusively and will not be guaranteed by any of our subsidiaries. Substantially all of our operations are conducted through our subsidiaries. As a result, our cash flow and ability to service our debt, including the notes, depend upon the earnings of our subsidiaries and the ability of our subsidiaries to distribute to us their earnings, loans or other payments. Our subsidiaries are separate legal entities that have no obligation to pay any amounts due under the notes or to make any funds available for such payments.

As a result, the notes will be effectively subordinated to all existing and future debt and other liabilities of our subsidiaries. In the event of a bankruptcy, liquidation or similar proceedings involving any of our subsidiaries, the creditors of that subsidiary will generally be entitled to payment of their claims from the assets of that subsidiary before any assets are made available for distribution to us, except to the extent that we may also have a claim as a creditor of that subsidiary, in which case our claims would still be subordinated to any security interests in, or mortgages on, the assets of that subsidiary and would be subordinate to any debt of that subsidiary that is senior to that held by us.

The notes will also be effectively subordinated to all of our future debt that is guaranteed by our subsidiaries to the extent of those guarantees. In the event of our bankruptcy, liquidation or similar proceeding, the holders of any such guaranteed debt would be entitled to require the subsidiary guarantors to pay that debt, while holders of the notes would not have any similar rights against those subsidiary guarantors.

In addition, the indenture governing the notes permits our subsidiaries to incur additional indebtedness, and does not contain any limitation on the amount of other liabilities, such as trade payables, that may be incurred by our subsidiaries. Thus, the amount of these liabilities may increase in the future.

As of June 30, 2024, our subsidiaries had approximately $1.8 million of outstanding indebtedness.

The notes will be subject to the prior claims of any future secured creditors.

The notes are senior unsecured obligations, ranking effectively junior to any secured indebtedness we may incur in the future. If we incur secured debt, our assets securing any such indebtedness will be subject to prior claims by our secured creditors. In the event of our bankruptcy, insolvency, liquidation, reorganization, dissolution or other winding up, or upon any acceleration of the notes, our assets that secure other indebtedness will be available to pay obligations on the notes only after all other such debt secured by those assets has been repaid in full. Any remaining assets will be available to you ratably with all of our other unsecured creditors, including trade creditors. If there are not sufficient assets remaining to pay all these creditors, then all or a portion of the notes then outstanding would remain unpaid.

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Our existing and future indebtedness may limit cash flow available to invest in the ongoing needs of our business, which could prevent us from fulfilling our obligations under the notes.

The indenture under which the notes will be issued will not limit the amount of indebtedness that we may incur. We also have the ability under our existing debt agreements to incur substantial additional indebtedness. Our level of indebtedness could have important consequences to you. For example, it could:

These risks increase as the level of our indebtedness increases. Our ability to make payments of principal of and interest on our indebtedness, including the notes, depends upon our future performance, which will be subject to general economic conditions, industry cycles and financial, business and other factors affecting our results of operations and financial condition, many of which are beyond our control. If we are unable to generate sufficient cash flow from operations in the future to service our debt (including the notes), we may be required to, among other things:

Additionally, any failure to meet required payments on our indebtedness, or failure to comply with any covenants in the instruments governing our indebtedness, could result in an event of default under the terms of those instruments. In the event of such default, the holders of such indebtedness could elect to declare all the amounts outstanding under such instruments to be due and payable. Any default under the agreements governing our indebtedness and the remedies sought by the holders of such indebtedness could render us unable to pay principal and interest on the notes and substantially decrease their value.

The terms of the indenture and the notes provide only limited protection against significant corporate events and other actions we may take that could adversely affect your investment in the notes.

While the indenture and the notes contain terms intended to provide protection to the holders of the notes upon the occurrence of certain events involving significant corporate transactions, such terms are limited and may not be sufficient to protect your investment in the notes. In addition, the definition of the term “Change of Control Triggering Event” does not cover a variety of transactions (such as acquisitions by us or recapitalizations) that could negatively affect the value of your notes. If we were to enter into a significant corporate transaction that would negatively affect the value of the notes but would not constitute a Change of Control Triggering Event, we would not be required to offer to repurchase your notes prior to their maturity.

Furthermore, the indenture for the notes does not:

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As a result of the foregoing, when evaluating the terms of the notes, you should be aware that the terms of the indenture and the notes do not restrict our ability to engage in, or to otherwise be a party to, a variety of corporate transactions, circumstances and events that could have an adverse impact on your investment in the notes.

We may not be able to repurchase the notes upon a Change of Control Triggering Event.

If a Change of Control Triggering Event occurs, unless we have exercised our option (or obligation, as the case may be) to redeem the notes as described under “Description of the Notes—Optional Redemption” or “Description of the Notes—Special Mandatory Redemption,” we will be required to make an offer to purchase the notes in cash at the redemption prices described in this prospectus supplement. However, we may not be able to repurchase the notes upon a Change of Control Triggering Event because we may not have sufficient funds to do so. Likewise, events similar to a Change of Control Triggering Event constitute or may constitute defaults or events of default under other existing or future indebtedness of ours and the occurrence of these events may permit the holders of such indebtedness to demand immediate repayment of such indebtedness or require that we offer to repurchase or repay such indebtedness. In addition, agreements governing indebtedness incurred in the future may restrict us from purchasing the notes in the event of a Change of Control Triggering Event. Any failure to purchase properly tendered notes would constitute an event of default under the indenture governing the notes, which could, in turn, cause an acceleration of our other indebtedness. See “Description of the Notes—Change of Control Offer.”

We may choose to redeem the notes prior to maturity.

We may redeem some or all of the notes at any time. See “Description of the Notes—Optional Redemption.” We may be required to redeem the notes in connection with a Special Mandatory Redemption. See “Description of the Notes—Special Mandatory Redemption.” If prevailing interest rates are lower at the time of redemption, you may not be able to reinvest the redemption proceeds in a comparable security at an interest rate as high as the interest rate of the notes being redeemed.

If the Mott Acquisition is not completed on or before the Special Mandatory Redemption End Date, we will be required to redeem the notes. If this occurs, you may realize a lower return on your investment than if the notes had been held through maturity.

If (i) the Mott Acquisition is not consummated on or before the Special Mandatory Redemption End Date, (ii) prior to the Special Mandatory Redemption End Date, the Mott Acquisition Agreement is terminated according to its terms without the closing of the Mott Acquisition or (iii) we otherwise notify the trustee in writing that we will not pursue the consummation of the Mott Acquisition, then we will be required to redeem the notes at a special mandatory redemption price equal to 101% of the aggregate principal amount of the notes, plus accrued and unpaid interest, if any, to, but excluding, the Special Mandatory Redemption Date (subject to the right of holders of the notes of record on the relevant record date to receive interest due on an interest payment date falling prior to the Special Mandatory Redemption Date). See “Description of the Notes—Special Mandatory Redemption.”

The net proceeds from this offering will not be deposited into an escrow account pending completion of the Mott Acquisition or any Special Mandatory Redemption, nor will we be required to grant any security interest or

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other lien on those proceeds to secure any redemption of the notes, and the indenture governing the notes will not impose any specific restrictions on our use of the proceeds prior to the consummation of the Mott Acquisition. Accordingly, the source of funds for any such mandatory redemption of the notes would be the proceeds that we have voluntarily retained or other sources of liquidity. If we are required to redeem the notes, the ability to pay the redemption price may be limited by our financial resources at the time. In addition, whether or not a Special Mandatory Redemption of the notes is ultimately triggered, the existence of these redemption provisions may adversely affect the trading prices of the notes until such time, if any, as the Mott Acquisition is consummated.

If we redeem the notes pursuant to the special mandatory redemption provisions, you may not be able to reinvest the redemption proceeds in a comparable security at an effective interest rate or return on investment as high as what you otherwise would have received on your notes being redeemed. Holders of the notes will have no right to opt out of the special mandatory redemption provisions of the notes.

Your decision to invest in the notes is made at the time of the offering of the notes. We will not be required to redeem the notes as long as the Mott Acquisition closes on or before the Special Mandatory Redemption End Date, even if between the closing of this offering and the closing of the Mott Acquisition we experience any changes (including any material changes) in our business or financial condition.

Changes in our credit ratings may adversely affect your investment in the notes.

Our credit ratings are an assessment by rating agencies of our ability to pay our debts when due. Consequently, real or anticipated changes in our credit ratings will generally affect the market value of the notes. These credit ratings may not reflect the potential impact of risks relating to the structure or marketing of the notes. Agency ratings are not a recommendation to buy, sell or hold the notes, and may be revised or withdrawn at any time by the rating agency. Each agency’s rating should be evaluated independently of any other agency’s rating.

Our existing debt agreements contain covenants that may limit our operations.

We completed a private placement of $100.0 million aggregate principal amount of 5.13% Senior Notes due June 13, 2028, pursuant to a note purchase agreement dated June 13, 2023. On November 1, 2022, we amended and restated that certain credit agreement we entered into on May 31, 2019, governing our $800 million revolving credit facility and our $200 million term credit facility due November 2027. On May 28, 2021, we completed a public offering of $500.0 million in aggregate principal amount of our 2.625% Senior Notes due June 2031, and on April 29, 2020, we completed a public offering of $500 million aggregate principal amount of our 3.00% Senior Notes due May 2030. Each of our existing debt agreements contains certain covenants restricting our operations and the operations of our subsidiaries, including covenants placing certain limits on permitted indebtedness of us or our subsidiaries and on the creation, incurrence, assumption or existence of certain liens on our property or the property of our subsidiaries. We are also required to maintain a minimum interest coverage ratio and maximum leverage ratio under the credit agreement governing our revolving credit facility and term credit facility, and the 2023 note purchase agreement. If any of these restrictions were to materially impair the operations and earnings of our subsidiaries, their cash distributions to us may be diminished and our ability to service our debt obligations, including the notes, may be adversely affected.

There may not be an active trading market for the notes.

There is no existing market for the notes, and we do not intend to apply for listing of the notes on any securities exchange or any automated quotation system. Accordingly, there can be no assurance that a trading market for the notes will ever develop or will be maintained. Further, there can be no assurance as to the liquidity of any market that may develop for the notes, your ability to sell your notes or the price at which you will be able to sell your notes. Future trading prices of the notes will depend on many factors, including but not limited to prevailing interest rates, our financial condition and results of operations, prospects for companies in our industry

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generally, the then-current ratings assigned to the notes and the market for similar securities. Any trading market that develops would be affected by many factors independent of and in addition to the foregoing, including:

The underwriters have advised us that they currently intend to make a market in the notes, but they are not obligated to do so and may cease market-making at any time without notice.

An increase in market interest rates could result in a decrease in the value of the notes.

The value of the securities prior to maturity will fluctuate based on many unpredictable factors. Inflationary pressures caused the Federal Reserve to increase interest rates in 2022 and 2023, although the Federal Reserve has indicated that there could be interest rate decreases in 2024. Increases in interest rates in the past have led to recessions of various lengths and intensities and any future interest rate increases may lead to such a recession in the near future. Such a recession or any other adverse changes in business and economic conditions generally or specifically in the markets in which we operate could affect our business.

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USE OF PROCEEDS

We estimate that the net proceeds from the offering will be approximately $495.0 million, after deducting the underwriting discount and commissions and our estimated offering expenses. We intend to use the net proceeds from this offering, together with available revolving credit facility borrowings and cash on hand, to (i) fund the cash consideration payable by us for the Mott Acquisition and (ii) pay fees and expenses in respect of the foregoing.

This offering is not conditioned upon the consummation of the Mott Acquisition, which, if completed, will occur subsequent to the closing of this offering, and we cannot assure you that the Mott Acquisition will be consummated on a timely basis, on the terms described herein, or at all. If (i) the Mott Acquisition is not consummated on or before the Special Mandatory Redemption End Date, (ii) prior to the Special Mandatory Redemption End Date, the Mott Acquisition Agreement is terminated according to its terms without the closing of the Mott Acquisition or (iii) we otherwise notify the trustee in writing that we will not pursue the consummation of the Mott Acquisition, then we will be required to redeem the notes at a special mandatory redemption price equal to 101% of the aggregate principal amount of the notes, plus accrued and unpaid interest, if any, to, but excluding, the Special Mandatory Redemption Date (subject to the right of holders of the notes of record on the relevant record date to receive interest due on an interest payment date falling prior to the Special Mandatory Redemption Date). See “Description of the Notes—Special Mandatory Redemption.”

The net proceeds from this offering will not be deposited into an escrow account pending completion of the Mott Acquisition or any Special Mandatory Redemption, nor will we be required to grant any security interest or other lien on those proceeds to secure any redemption of the notes.

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CAPITALIZATION

The following table sets forth our unaudited capitalization as of June 30, 2024, and as adjusted to give effect to the issuance and sale of the notes and the use of the proceeds from this offering as set forth under “Use of Proceeds” in this prospectus supplement. This table should be read in conjunction with our historical consolidated financial statements, including the related notes, which are incorporated by reference in this prospectus supplement and the accompanying prospectus. See “Where You Can Find More Information” in this prospectus supplement or the accompanying prospectus.

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DESCRIPTION OF THE NOTES

The notes will constitute a series of debt securities to be issued under the indenture, dated as of December 6, 2010 (the “base indenture”) between us and Computershare Trust Company, N.A., as successor to Wells Fargo Bank, National Association, as trustee (the “trustee”), as further supplemented by a fifth supplemental indenture to be dated as of August 21, 2024 (the “fifth supplemental indenture” and, together with the base indenture, the “indenture”). The following description is only a summary of certain provisions of the notes and the indenture. You should read these documents in their entirety because they, and not this description, define your rights as holders of the notes. The following summary does not purport to be complete and is subject to, and is qualified in its entirety by reference to, the Trust Indenture Act of 1939, as amended (the “TIA”), and to all of the provisions of the indenture and those terms made a part of the indenture by reference to the TIA. Unless the context requires otherwise, all references to “we,” “us,” “our,” and the “Company” in this section refer solely to IDEX Corporation and not to its subsidiaries.

The following description of the particular terms of the notes offered hereby supplements the general description of debt securities set forth in the accompanying prospectus.

General

The notes will be issued in an initial aggregate principal amount of $500,000,000 and will mature on September 1, 2029. The notes will be issued only in fully registered form without coupons in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof. The notes will not be entitled to any sinking fund.

Interest on the notes will accrue at the rate per annum shown on the cover of this prospectus supplement from August 21, 2024, or from the most recent date to which interest has been paid or provided for, payable semi-annually on March 1 and of September 1 each year, commencing March 1, 2025, to the persons in whose names the notes are registered in the security register at the close of business on the February 15 or August 15 preceding the relevant interest payment date. Interest will be computed on the notes on the basis of a 360-day year of twelve 30-day months.

The indenture does not limit the amount of notes that we may issue. We may, without the consent of the existing holders of the notes, issue additional debt securities under the indenture from time to time in one or more series, each in an amount authorized prior to issuance. We will not issue any such additional debt securities as part of the same series as the notes unless the notes and any such additional debt securities would be fungible with each other for United States federal income tax purposes.

The indenture does not limit our ability, or the ability of our subsidiaries, to incur or guarantee additional unsecured indebtedness. The indenture and the terms of the notes will not contain any covenants (other than those described herein) designed to afford holders of any notes protection in a highly leveraged or other transaction involving us that may adversely affect holders of the notes.

There are no public trading markets for the notes, and we do not intend to apply for listing of the notes on any national securities exchange or for quotation of the notes on any automated dealer quotation system.

Ranking

The notes will be our senior unsecured obligations and will be:

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The notes are not guaranteed by any of our subsidiaries and will therefore be structurally subordinated to all of the existing and future indebtedness and other liabilities of our subsidiaries.

As of June 30, 2024, we had outstanding indebtedness of approximately $1.3 billion that ranks equally with the notes and no secured indebtedness outstanding, and our subsidiaries had approximately $1.8 million of outstanding indebtedness.

Optional Redemption

Prior to the Par Call Date, we may redeem the notes at our option, in whole or in part, at any time and from time to time, upon written notice as provided in the indenture, at a redemption price (expressed as a percentage of principal amount and rounded to three decimal places) equal to the greater of:

plus, in either case, accrued and unpaid interest thereon to, but excluding, the redemption date.

On or after the Par Call Date, we may redeem the notes, in whole or in part, at any time and from time to time, upon written notice as provided in the indenture, at a redemption price equal to 100% of the principal amount of the notes being redeemed plus accrued and unpaid interest thereon to, but excluding, the redemption date.

“Treasury Rate” means, with respect to any redemption date, the yield determined by us in accordance with the following two paragraphs.

The Treasury Rate shall be determined by us after 4:15 p.m., New York City time (or after such time as yields on U.S. government securities are posted daily by the Board of Governors of the Federal Reserve System), on the third business day preceding the redemption date based upon the yield or yields for the most recent day that appear after such time on such day in the most recent statistical release published by the Board of Governors of the Federal Reserve System designated as “Selected Interest Rates (Daily) — H.15” (or any successor designation or publication) (“H.15”) under the caption “U.S. government securities — Treasury constant maturities — Nominal” (or any successor caption or heading) (“H.15 TCM”). In determining the Treasury Rate, we shall select, as applicable: (1) the yield for the Treasury constant maturity on H.15 exactly equal to the period from the redemption date to the Par Call Date (the “Remaining Life”); or (2) if there is no such Treasury constant maturity on H.15 exactly equal to the Remaining Life, the two yields — one yield corresponding to the Treasury constant maturity on H.15 immediately shorter than and one yield corresponding to the Treasury constant maturity on H.15 immediately longer than the Remaining Life — and shall interpolate to the Par Call Date on a straight-line basis (using the actual number of days) using such yields and rounding the result to three decimal places; or (3) if there is no such Treasury constant maturity on H.15 shorter than or longer than the Remaining Life, the yield for the single Treasury constant maturity on H.15 closest to the Remaining Life. For purposes of this paragraph, the applicable Treasury constant maturity or maturities on H.15 shall be deemed to have a maturity date equal to the relevant number of months or years, as applicable, of such Treasury constant maturity from the redemption date.

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If on the third business day preceding the redemption date H.15 TCM is no longer published we shall calculate the Treasury Rate based on the rate per annum equal to the semi-annual equivalent yield to maturity at 11:00 a.m., New York City time, on the second business day preceding such redemption date of the United States Treasury security maturing on, or with a maturity that is closest to, the Par Call Date, as applicable. If there is no United States Treasury security maturing on the Par Call Date but there are two or more United States Treasury securities with a maturity date equally distant from the Par Call Date, one with a maturity date preceding the Par Call Date and one with a maturity date following the Par Call Date, we shall select the United States Treasury security with a maturity date preceding the Par Call Date. If there are two or more United States Treasury securities maturing on the Par Call Date or two or more United States Treasury securities meeting the criteria of the preceding sentence, we shall select from among these two or more United States Treasury securities the United States Treasury security that is trading closest to par based upon the average of the bid and asked prices for such United States Treasury securities at 11:00 a.m., New York City time. In determining the Treasury Rate in accordance with the terms of this paragraph, the semi-annual yield to maturity of the applicable United States Treasury security shall be based upon the average of the bid and asked prices (expressed as a percentage of principal amount) at 11:00 a.m., New York City time, of such United States Treasury security, and rounded to three decimal places.

Our actions and determinations in determining the redemption price shall be conclusive and binding for all purposes, absent manifest error.

Notice of redemption will be mailed or sent electronically pursuant to applicable DTC procedures at least 10 but not more than 60 days before the redemption date to each holder of record of the notes to be redeemed at its registered address. If less than all of the notes are to be redeemed at any time, and the notes are global securities, the notes to be redeemed will be selected by DTC in accordance with its standard procedures. If the notes to be redeemed are not global securities then held by DTC, the trustee will select notes to be redeemed on a pro rata basis, by lot, or by any other method the trustee deems fair and appropriate. The notice of redemption for the notes will state, among other things, the amount of notes to be redeemed, the redemption date, the manner in which the redemption price will be calculated, the place or places that payment will be made upon presentation and surrender of notes to be redeemed and any conditions precedent to the effectiveness of the redemption. Unless we default in the payment of the redemption price, interest will cease to accrue on any notes that have been called for redemption at the redemption date.

Special Mandatory Redemption

If (i) the Mott Acquisition is not consummated on or before the later of (x) November 20, 2024 or (y) such later date to which the outside date under the Mott Acquisition Agreement as in effect on the closing date of this offering may be extended in accordance with the terms thereof, any such extension to be set forth in an Officer’s Certificate (as defined below) delivered to the trustee prior to the close of business on November 20, 2024 (the later of (x) and (y) being referred to herein as the “Special Mandatory Redemption End Date”), (ii) prior to the Special Mandatory Redemption End Date, the Mott Acquisition Agreement is terminated according to its terms without the closing of the Mott Acquisition or (iii) we otherwise notify the trustee in writing that we will not pursue the consummation of the Mott Acquisition (any event in clause (i), (ii) or (iii), a “Special Mandatory Redemption Event”), then we will be required to redeem the notes at a special mandatory redemption price equal to 101% of the aggregate principal amount of the notes, plus accrued and unpaid interest, if any, to, but excluding, the Special Mandatory Redemption Date (subject to the right of holders of the notes of record on the relevant record date to receive interest due on an interest payment date falling prior to the Special Mandatory Redemption Date) (the “Special Mandatory Redemption Price”) (such redemption, a “Special Mandatory Redemption”). Unless we default in payment of the Special Mandatory Redemption Price, on and after such Special Mandatory Redemption Date, interest will cease to accrue on the notes to be redeemed.

In the event that we become obligated to redeem the notes pursuant to the Special Mandatory Redemption, we will promptly, and in any event not more than five business days after the Special Mandatory Redemption

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Event, deliver notice to the trustee of the Special Mandatory Redemption and the date upon which the notes will be redeemed (the “Special Mandatory Redemption Date”), which date shall be no later than the tenth business day following the date of such notice unless some longer minimum period may be required by DTC (or any successor depositary), together with a notice of Special Mandatory Redemption for the trustee to deliver to each registered holder of notes. The trustee will then promptly mail or electronically deliver (or otherwise transmit in accordance with the depositary’s procedures) such notice of Special Mandatory Redemption to each registered holder of the notes.

On or before the Special Mandatory Redemption Date, we will pay to a paying agent for payment to each holder of the notes the Special Mandatory Redemption Price for such holder’s notes.

Failure to make the Special Mandatory Redemption, if required in accordance with the terms described above, will constitute an event of default with respect to the notes.

The net proceeds from this offering will not be deposited into an escrow account pending completion of the Mott Acquisition or any Special Mandatory Redemption, nor will we be required to grant any security interest or other lien on those proceeds to secure any redemption of the notes.

Upon the consummation of the Mott Acquisition, the foregoing provisions regarding Special Mandatory Redemption will cease to apply. For the purposes of the Mott Acquisition, the Mott Acquisition will be deemed consummated if the closing under the Mott Acquisition Agreement occurs, including after giving effect to any amendments or modifications to the Mott Acquisition Agreement or waivers thereunder.

For purposes of this Description of the Notes, the following definitions apply:

“Mott” means Mott Corporation and its subsidiaries.

“Mott Acquisition” means the acquisition by IDEX Corporation of Mott, pursuant to the Mott Acquisition Agreement.

“Mott Acquisition Agreement” means the Stock Purchase Agreement, dated as of July 23, 2024, among Mott Corporation, Mott Corporation Employee Stock Ownership Trust, which is maintained pursuant to and in connection with the Mott Corporation Employee Stock Ownership Plan, acting through GreatBanc Trust Company, solely as Trustee of the Trust, IDEX Holdings, Inc. and, solely for purposes of Section 10.15 thereof, IDEX Corporation, as may be amended or modified or any provision thereof waived from time to time.

Change of Control Offer

If a Change of Control Triggering Event occurs, unless we have exercised our option (or obligation, as the case may be) to redeem the notes as described under “—Optional Redemption” or “—Special Mandatory Redemption,” we will be required to make an offer (a “Change of Control Offer”) to each holder of the notes to repurchase all or any part (equal to $2,000 or an integral multiple of $1,000 in excess thereof) of that holder’s notes on the terms set forth in the notes.

In a Change of Control Offer, we will be required to offer payment in cash equal to 101% of the aggregate principal amount of notes repurchased, plus accrued and unpaid interest, if any, on the notes repurchased to, but not including, the repurchase date (a “Change of Control Payment”). Within 30 days following any Change of Control Triggering Event or, at our option, prior to any Change of Control, but after public announcement of the transaction that constitutes or may constitute the Change of Control, a notice will be mailed or sent electronically pursuant to applicable DTC procedures to holders of the notes with a copy to the trustee describing the transaction that constitutes or may constitute the Change of Control Triggering Event and offering to repurchase such notes on the repurchase date specified in the applicable notice, which date will be no earlier than 10 days

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and no later than 60 days from the date on which such notice is mailed or sent (a “Change of Control Payment Date”).

The notice will, if mailed or sent prior to the date of consummation of the Change of Control, state that the Change of Control Offer is conditioned on the Change of Control Triggering Event occurring prior to or on the applicable Change of Control Payment Date specified in the notice.

On each Change of Control Payment Date, we will, to the extent lawful:

We will not be required to make a Change of Control Offer upon the occurrence of a Change of Control Triggering Event if a third party makes such an offer in the manner, at the times and otherwise in compliance with the requirements for an offer made by us, and the third party repurchases all notes properly tendered and not withdrawn under its offer.

We will comply with the requirements of Rule 14e-1 under the Exchange Act and any other securities laws and regulations thereunder to the extent those laws and regulations are applicable in connection with the repurchase of the notes as a result of a Change of Control Triggering Event. To the extent that the provisions of any such securities laws or regulations conflict with the Change of Control Offer provisions of the notes, we will comply with those securities laws and regulations and will not be deemed to have breached our obligations under the Change of Control Offer provisions of the notes by virtue of any such conflict.

For purposes of the Change of Control Offer provisions of the notes, the following definitions will be applicable:

“Change of Control” means the occurrence of any of the following:

(a) the direct or indirect sale, lease, transfer, conveyance or other disposition (other than by way of merger or consolidation), in one or more series of related transactions, of all or substantially all of our assets and our subsidiaries’ assets, taken as a whole, to any person, other than us or one of our subsidiaries; provided, however, that none of the circumstances in this clause (a) will be a Change of Control if the persons that beneficially own our Voting Stock immediately prior to the transaction own, directly or indirectly, shares with a majority of the total voting power of all outstanding voting securities of the surviving or transferee person that are entitled to vote generally in the election of that person’s board of directors, managers or trustees immediately after the transaction;

(b) the consummation of any transaction (including, without limitation, any merger or consolidation), the result of which is that any “person” (as that term is used in Section 13(d)(3) of the Exchange Act) becomes the “beneficial owner” (as defined in Rules 13d-3 and 13d-5 under the Exchange Act), directly or indirectly, of more than 50% of our outstanding Voting Stock or other Voting Stock into which our Voting Stock is reclassified, consolidated, exchanged or changed, measured by voting power rather than number of shares;

(c) we consolidate with, or merge with or into, any person, or any person consolidates with, or merges with or into, us, in any such event pursuant to a transaction in which any of our outstanding Voting Stock or the

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Voting Stock of such other person is converted into or exchanged for cash, securities or other property, other than any such transaction where the shares of our Voting Stock outstanding immediately prior to such transaction constitute, or are converted into or exchanged for, a majority of the Voting Stock of the surviving person or any direct or indirect parent company of the surviving person immediately after giving effect to such transaction; or

(d) the adoption of a plan relating to the liquidation or dissolution of the Company.

As used in this definition, the term “person” has the meaning given thereto in Section 13(d)(3) of the Exchange Act.

“Change of Control Triggering Event” means the occurrence of both a Change of Control and a Rating Event.

“Fitch” means Fitch Ratings Ltd. and its successors.

“Investment Grade” means a rating equal to or higher than BBB- (or the equivalent) by Fitch, Baa3 (or the equivalent) by Moody’s and BBB- (or the equivalent) by S&P, and the equivalent Investment Grade credit rating from any replacement Rating Agency or Rating Agencies selected by us.

“Moody’s” means Moody’s Investors Service, Inc., and its successors.

“Rating Agencies” means (a) each of Fitch, Moody’s and S&P; and (b) if any of Fitch, Moody’s or S&P ceases to rate the notes or fails to make a rating of the notes publicly available for reasons outside of our control, a “nationally recognized statistical rating organization” within the meaning of Rule 15c3-1 (c)(2)(vi)(F) under the Exchange Act selected by us as a replacement agency for Fitch, Moody’s or S&P, or all of them, as the case may be.

“Rating Event” means a decrease in the ratings of the notes below Investment Grade by at least two of the three Rating Agencies on any date from the date that is 60 days prior to the date of the first public notice of an arrangement that could result in a Change of Control until the end of the 60-day period following the consummation of such Change of Control (which period will be extended so long as the rating of the notes is under publicly announced consideration for possible downgrade by any of the Rating Agencies).

“S&P” means S&P Global Ratings and its successors.

“Voting Stock” means, with respect to any specified “person” (as that term is used in Section 13(d)(3) of the Exchange Act) as of any date, the Capital Stock of such person that is at the time entitled to vote generally in the election of the board of directors of such person.

The definition of Change of Control and the covenant described under “Limitation on Consolidation, Merger, Conveyance or Transfer” below include a phrase relating to the direct or indirect sale, transfer, conveyance or other disposition of “all or substantially all” of our assets and the assets of our subsidiaries, taken as a whole. Although there is a limited body of case law interpreting the phrase “substantially all,” there is no precise definition of the phrase under applicable law. Accordingly, the ability of a holder of notes to require us to repurchase such holder’s notes as a result of a sale, transfer, conveyance of other disposition of less than all of our and our subsidiaries’ assets, taken as a whole, to any person or group of persons may be uncertain.

Certain Covenants

Limitations on Liens

We will not, and will not permit any Restricted Subsidiary to, directly or indirectly, create, assume or permit to exist, any Lien, other than Permitted Liens, on any Principal Property, or upon Capital Stock or Debt of any

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Restricted Subsidiary and owned by us or any Subsidiary, now or hereafter acquired, to secure Debt, without effectively providing concurrently that the notes are secured equally and ratably with such Debt, for so long as such Debt shall be so secured.

“Permitted Liens” means:

(a) Liens existing at the date of the indenture;

(b) Liens in favor of us or a Restricted Subsidiary;

(c) Liens on any property existing at the time of the acquisition thereof;

(d) Liens on any property of a Person or its subsidiaries existing at the time such Person is consolidated with or merged into the Company or a Restricted Subsidiary, or Liens on any property of a Person existing at the time such Person becomes a Restricted Subsidiary;

(e) Liens to secure all or part of the cost of acquisition (including Liens created as a result of an acquisition by way of Capital Lease), construction, development or improvement of the underlying property, or to secure Debt incurred to provide funds for any such purposes, provided, that the commitment of the creditor to extend the credit secured by any such Lien shall have been obtained not later than 12 months after the later of (A) the completion of the acquisition, construction, development or improvement of such property and (B) the placing in operation of such property or of such property as so constructed, developed or improved;

(f) Liens securing industrial revenue, pollution control or similar bonds; and

(g) any extension, renewal or replacement (including successive extensions, renewals and replacements), in whole or in part, of any Lien referred to in any of clauses (a), (c), (d) or (e) that would not otherwise be permitted pursuant to any of clauses (a) through (f), to the extent that (A) the principal amount of Debt secured thereby and not otherwise permitted to be secured pursuant to any of clauses (a) through (f) does not exceed the principal amount of Debt, plus any premium or fee payable in connection with any such extension, renewal or replacement, so secured at the time of any such extension, renewal or replacement, except that where the Debt so secured at the time of any such extension, renewal or replacement was incurred for the sole purpose of financing a specific project; and (B) the property that is subject to the Lien serving as an extension, renewal or replacement is limited to some or all of the property that was subject to the Lien so extended, renewed or replaced.

Notwithstanding the restrictions described above, we and our Restricted Subsidiaries may, directly or indirectly, create, assume or permit to exist any Lien that would otherwise be subject to the restrictions set forth in the first paragraph of this section without equally and ratably securing the notes if, at the time of such creation, assumption or permission, after giving effect thereto and to the retirement of any Debt which is concurrently being retired, the aggregate principal amount of outstanding Debt secured by Liens which would otherwise be subject to such restrictions (not including Permitted Liens) plus all Attributable Debt of the Company and our Restricted Subsidiaries in respect of Sale and Leaseback Transactions with respect to any Principal Property (not including such transactions described under any of clauses (a) through (g) as set forth below under “—Sale and Leaseback Transactions”), does not exceed 15% of Consolidated Net Tangible Assets.

Limitations on Sale and Leaseback Transactions

We will not, and will not permit any Restricted Subsidiary to, enter into any Sale and Leaseback Transaction with respect to any Principal Property owned by us or such Restricted Subsidiary, unless:

(a) the Sale and Leaseback Transaction is solely with us or a Subsidiary;

(b) the lease in such Sale and Leaseback Transaction is for a period not in excess of three years;

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(c) the lease in such Sale and Leaseback Transaction secures or relates to industrial revenue, pollution control or similar bonds;

(d) the Sale and Leaseback Transaction is entered into prior to or within 12 months after the purchase or acquisition of the Principal Property which is the subject of such Sale and Leaseback Transaction;

(e) the Sale and Leaseback Transaction involving property of a Person existing at the time such Person is merged into or consolidated with us or a Subsidiary or at the time of a sale, lease or other disposition of the properties of a Person as an entirety or substantially as an entirety to us or a Subsidiary;

(f) the proceeds of the Sale and Leaseback Transaction are at least equal to the fair value (as determined by our Board of Directors in good faith) of the Principal Property leased pursuant to such Sale and Leaseback Transaction, so long as within 180 days of the effective date of such Sale and Leaseback Transaction, we or such Restricted Subsidiary apply (or irrevocably commit to an escrow account for the purpose or purposes hereinafter mentioned) an amount equal to the greater of (A) net proceeds of such sale, and (B) the Attributable Debt of the Company and our Restricted Subsidiaries in respect of such Sale and Leaseback Transaction to either (x) the purchase of property which will constitute a Principal Property having a fair value at least equal to the fair value of the Principal Property leased, or (y) the retirement or repayment (other than any mandatory retirement, mandatory prepayment or sinking fund payment or by payment at maturity) of any Funded Debt of the Company or a Restricted Subsidiary (other than Funded Debt that is subordinated to the notes) or preferred stock of any Subsidiary (other than any such Debt owed to or preferred stock owned by us or any Subsidiary); provided, however, that in lieu of applying an amount equivalent to all or any part of such net proceeds to such retirement or repayment (or committing such an amount to an escrow account for such purpose), we or the Restricted Subsidiary may deliver to the trustee outstanding notes and thereby reduce the amount to be applied pursuant to (y) of this clause (f) by an amount equivalent to the aggregate principal amount of the notes so delivered;

(g) the Sale and Leaseback Transaction involving the extension, renewal or replacement (or successive extensions, renewals or replacements) in whole or in part of a lease pursuant to a Sale and Leaseback Transaction referred to in the foregoing clauses (a) to (f), inclusive; provided, however, that such lease extension, renewal or replacement shall be limited to all or any part of the same property leased under the lease so extended, renewed or replaced (plus improvements to such property); or

(h) the Attributable Debt of the Company and our Restricted Subsidiaries in respect of such Sale and Leaseback Transaction and all other Sale and Leaseback Transactions with respect to any Principal Property (not including any Sale and Leaseback Transactions described under any of clauses (a) through (g) of this sentence), plus the aggregate principal amount of outstanding Debt secured by Liens upon Principal Properties or Capital Stock or Debt of any Restricted Subsidiary and owned by us or any Subsidiary then outstanding (not including any such Debt secured by Permitted Liens) which do not secure such outstanding securities issued under the indenture equally and ratably with (or on a basis that is prior to) the other Debt secured thereby, would not exceed 15% of Consolidated Net Tangible Assets.

Consolidation, Merger, Sale or Conveyance

We will not consolidate with or merge with any other Person, or sell, convey, transfer or lease all or substantially all of our assets to any Person, unless:

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This covenant will not apply to any sale, assignment, transfer, conveyance, lease or other disposition of assets solely between or among us and our U.S. Subsidiaries.

In the event that we consolidate with or merge with another Person or sell substantially all of our assets to any other Person, the surviving entity (if other than us) will be substituted for us under the indenture, and we will be discharged from all of our obligations under the indenture.

In addition, in connection with any such transaction, we will deliver to the trustee an Officer’s Certificate and an opinion of counsel, each stating that such consolidation, merger, sale, conveyance, transfer or lease and, if a supplemental indenture is required in connection with such transaction, such supplemental indenture complies with the indenture and that all conditions precedent contained in the indenture relating to such transaction have been complied with.

Certain Definitions

For purposes of the above covenants and “—Events of Default” below, the following definitions will be applicable:

“Attributable Debt” with respect to a Sale and Leaseback Transaction with respect to any Principal Property, the lesser of: (a) the fair market value of such property (as determined by our Board of Directors in good faith); or (b) the present value of the total net amount of rent required to be paid under such lease during the remaining term thereof (including any period for which such lease has been extended and excluding any unexercised renewal or other extension options exercisable by the lessee, and excluding amounts on account of maintenance and repairs, services, taxes and similar charges and contingent rents), discounted at the rate of interest set forth or implicit in the terms of such lease (or, if not practicable to determine such rate, the weighted average interest rate per annum borne by the notes) compounded semi-annually. In the case of any lease which is terminable by the lessee upon the payment of a penalty, such net amount will be the lesser of the net amount determined assuming termination upon the first date such lease may be terminated (in which case the net amount will also include the amount of the penalty, but no rent will be considered as required to be paid under such lease subsequent to the first date upon which it may be so terminated) or the net amount determined assuming no such termination.

“Capital Lease” means any lease of any Principal Property that is or should be accounted for as a capital lease on the consolidated balance sheet of the Company and our Subsidiaries prepared in accordance with GAAP.

“Capital Stock” means and includes any and all shares, interests, participations or other equivalents (however designated) of ownership in a corporation or other Person.

“Consolidated Net Tangible Assets” means the aggregate amount of assets (less applicable reserves and other properly deductible items) after deducting therefrom (a) all current liabilities (excluding any Debt of less than 12 months from the date of our most recent consolidated balance sheet but which by its terms is renewable or extendable beyond 12 months from such date at our option) and (b) all goodwill, trade names, patents, unamortized debt discount and expense and any other like intangibles, all as set forth on our most recent consolidated balance sheet and determined in accordance with GAAP.

“Debt” means with respect to a Person all obligations of such Person for borrowed money and all such obligations of any other Person for borrowed money guaranteed by such Person.

“Funded Debt” means any Debt maturing by its terms more than one year from its date of issuance (notwithstanding that any portion of such Debt is included in current liabilities).

“Officer’s Certificate” means a certificate signed by the chief executive officer, any vice president, the chief financial officer, the controller, the treasurer, any assistant treasury, the secretary or any assistant secretary of the Company and delivered to the trustee.

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“GAAP” means generally accepted accounting principles as in effect from time to time in the United States.

“Lien” means any mortgage, pledge, security interest, lien, charge or other encumbrance.

“Person” means any individual, corporation, partnership, limited partnership, limited liability company, joint venture, association, joint stock company, trust, unincorporated organization or government or any agency or political subdivision thereof.

“Principal Property” means any manufacturing plant, warehouse, office building or parcel of real property, including fixtures but excluding leases and other contract rights which might otherwise be deemed real property, owned or leased by us or any of our Subsidiaries, whether owned or leased on the date of the indenture or thereafter acquired, that has a gross book value (determined in accordance with GAAP) in excess of 2% of the Consolidated Net Tangible Assets of the Company and our consolidated subsidiaries. Any plant, warehouse, office building or parcel of real property or portion thereof which our board of directors determines in good faith is not of material importance to the business conducted by us and our subsidiaries taken as a whole will not be a Principal Property.

“Restricted Subsidiary” means any Subsidiary of the Company which owns or leases Principal Property;

“Sale and Leaseback Transaction” means any arrangement with any Person relating to property now owned or hereafter acquired whereby we or any Restricted Subsidiary transfers such property to another Person and we or the Restricted Subsidiary lease or rent it from such Person.

“Subsidiary” means any corporation, partnership or other legal entity (a) the accounts of which are consolidated with ours in accordance with GAAP and (b) of which, in the case of a corporation, more than 50% of the outstanding voting stock is owned, directly or indirectly, by us or by one or more other subsidiaries, or by us and one or more other subsidiaries or, in the case of any partnership or other legal entity, more than 50% of the ordinary equity capital interests is, at the time, directly or indirectly owned or controlled by us or by one or more of the subsidiaries or by us and one or more of the subsidiaries.

Events of Default

You will have special rights if an event of default occurs and is not cured, as further described in the section “Events of Default” in the accompanying prospectus. The following will be “Events of Default” under the indenture with respect to the notes:

(a) default in the payment of any interest on any note when it becomes due and payable, and continuance of such default for a period of 30 days (unless the entire amount of such payment is deposited by us with the trustee or with a paying agent prior to the expiration of such period of 30 days);

(b) default in the payment of principal of or premium, if any, on any note when due and payable;

(c) default in the performance or breach of any covenant or warranty of the Company in the indenture (other than a covenant or warranty that has been included in the indenture solely for the benefit of a series of debt securities other than the notes), which default continues uncured for a period of 90 days after written notice to us by the trustee or to us and the trustee by the holders of not less than 25% in principal amount of the outstanding notes as provided in the indenture;

(d) certain events of bankruptcy, insolvency or reorganization with respect to us; or

(e) (i) a default occurs under any instrument under which there is outstanding, or by which there may be secured or evidenced, any indebtedness of the Company for money borrowed by the Company (other than

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non-recourse indebtedness) which results in acceleration of, or non-payment at maturity (after giving effect to any applicable grace period) of, such indebtedness in an amount exceeding $50,000,000, in which case the Company shall immediately give notice to the trustee of such acceleration or non-payment and (ii) there shall have been a failure to cure such default or to discharge such defaulted indebtedness within ten days after notice thereof to the Company by the trustee or to the Company and the trustee by the holders of at least 25% in aggregate principal amount of the notes then Outstanding; provided, however, that no such Event of Default described in this clause (e) shall exist as long as the Company is contesting any such default or acceleration in good faith and by appropriate proceedings.

Defeasance and Discharge

Defeasance

The term defeasance means we are discharged from some or all of our obligations under the indenture. If we irrevocably deposit in trust with the trustee under the indenture any combination of money or government securities in an amount sufficient in the opinion of a nationally recognized investment bank, appraisal firm or firm of independent public accountants expressed in a written certification thereof delivered to the trustee, to make payments on the notes under the indenture on the dates those payments are due, then, at our option:

If the notes are defeased, the holders of the notes will not be entitled to the benefits of the indenture, except for obligations to register the transfer or exchange of notes, replace stolen, lost or mutilated notes or maintain paying agencies and hold money for payment in trust.

We will be required to deliver to the trustee an opinion of counsel that the deposit and related defeasance would not cause the beneficial owners of the notes to recognize income, gain or loss for United States federal income tax purposes and that the beneficial owners would be subject to United States federal income tax on the same amounts, in the same manner and at the same times as would have been the case if the deposit and related defeasance had not occurred. If we elect legal defeasance, the opinion of counsel must be based upon a ruling from the United States Internal Revenue Service or a change in law to that effect.

Satisfaction and Discharge

In addition, we may discharge our obligations with respect to the notes and the indenture when:

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With respect to the first and second bullet points, only our obligations to compensate and indemnify the trustee and our right to recover unclaimed money held by the trustee under the indenture will survive.

With respect to the third bullet point, certain rights and obligations under the indenture (such as our obligation to maintain an office or agency, to have moneys held for payment in trust, to register the transfer or exchange of the notes, to deliver the notes for replacement or to be canceled, to compensate and indemnify the trustee and to appoint a successor trustee, and our right to recover unclaimed money held by the trustee) will survive until the notes are no longer outstanding. Thereafter, only our obligations to compensate and indemnify the trustee and our right to recover unclaimed money held by the trustee will survive.

Trustee

Computershare Trust Company, N.A., as successor to Wells Fargo Bank, National Association, is the trustee under the indenture. Initially, the trustee will also act as the paying agent, registrar and custodian for the global securities representing the notes. The trustee shall not be responsible for determining whether any Change of Control Triggering Event has occurred and whether any Change of Control Offer with respect to the notes is required. The trustee shall not be responsible for monitoring our rating status or making any request upon any Rating Agency.

Computershare Trust Company, N.A., in each of its capacities, including without limitation as trustee, paying agent, registrar and custodian, assumes no responsibility and will have no liability for the accuracy, correctness, adequacy, or completeness of the information concerning any other party contained in this document or the related documents, or for any failure by us or any other party to disclose events that may have occurred and may affect the significance, correctness, adequacy, completeness, or accuracy of such information. The trustee, in each of its capacities, will be entitled to those certain rights, privileges, immunities, indemnities, limitations of liability and protections, as more fully set forth in the indenture. We maintain and may maintain banking relationships in the ordinary course of business with the trustee and its affiliates.

Governing Law

The indenture and the notes will be governed by, and construed in accordance with, the laws of the State of New York.

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BOOK-ENTRY SYSTEM, DELIVERY AND FORM

The notes will be issued in the form of one or more debt securities in global, fully registered form (“global securities”), without interest coupons. Each such global security will be deposited with or on behalf of DTC and registered in the name of DTC or a nominee of DTC (we sometimes refer to DTC or any other depositary for the global securities as the “Depositary”).

Investors may hold their interests in a global security directly through DTC if they are direct participants (as defined below) or indirectly through organizations that are DTC participants (as defined below). Except in the limited circumstances described below, holders of beneficial interests in the global securities will not be entitled to receive debt securities in definitive, certificated form (“certificated securities”) or to have debt securities registered in their names.

We understand that DTC is a limited-purpose trust company organized under the New York Banking Law, a “banking organization” within the meaning of the New York Banking Law, a member of the Federal Reserve System, a “clearing corporation” within the meaning of the New York Uniform Commercial Code and a “clearing agency” registered pursuant to the provisions of Section 17A of the Exchange Act. DTC holds securities of institutions that have accounts with DTC (“direct participants”) to facilitate the clearance and settlement of securities transactions among its participants through electronic book-entry changes in accounts of such participants, thereby eliminating the need for physical movement of securities certificates. DTC’s direct participants include brokers, dealers, banks, trust companies, clearing corporations and certain other organizations and may include underwriters, agents or dealers involved in the distribution of the securities referred to in this prospectus. Indirect access to DTC’s book-entry system is also available to other organizations (“indirect participants” and, together with direct participants, “participants”), such as brokers, dealers, banks, trust companies and clearing corporations, that clear through or maintain a custodial relationship with a direct participant, whether directly or indirectly. The rules applicable to DTC and its direct participants are on file with the SEC.

Purchases of debt securities evidenced by global securities must be made by or through participants. Upon the issuance of a global security, DTC will credit, on its book-entry registration and transfer system, the respective principal amounts of the individual beneficial interests in the global security to the accounts of the applicable direct participants. Ownership of beneficial interests in each global security will be limited to participants or persons that hold interests through participants. Ownership of beneficial interests in each global security will be shown on, and the transfer of those ownership interests will be effected only through, records maintained by DTC (with respect to direct participants’ interests) and by its direct and indirect participants (with respect to the interests of beneficial owners).

So long as DTC or its nominee is the registered holder of a global security, DTC or such nominee, as the case may be, will be considered the sole holder and owner of the debt securities represented by such global security for all purposes under the indenture and such debt securities. Any notices required to be given to the holders while the notes are global securities will be given only to DTC. Owners of beneficial interests in a global security will not be considered the owners or holders of the debt securities under the indenture, will not be able to transfer those beneficial interests except in accordance with the procedures of DTC and its participants and, except under the limited circumstances set forth below, will not be entitled to receive certificated securities or to have debt securities registered in their names. Accordingly, each owner of a beneficial interest in a global security must rely on the procedures of DTC and, if such person is not a direct participant, on the procedures of the participants through which it owns its beneficial interest to exercise any rights of a holder of debt securities under the indenture. We understand that, under existing industry practice, in the event owners of beneficial interests in global securities wish to take any action that DTC or its nominee, as the holder of such global securities, is entitled to take, DTC would authorize the applicable participants to take such action, and that such participants would authorize beneficial owners owning through such participants to take such action or would otherwise act upon the instructions of such beneficial owners. Because DTC can only act on behalf of direct

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participants, who in turn act on behalf of others, the ability of a person having a beneficial interest in a global security to pledge that interest to persons that do not participate in the DTC system, or otherwise to take actions in respect of that interest, may be impaired by the lack of a physical certificate representing that interest.

All payments on the debt securities represented by a global security registered in the name of DTC or its nominee will be made to DTC or its nominee, as the case may be, as the registered holder of the global security.

We expect that DTC or its nominee, upon receipt of any payment of principal of, or premium or interest, if any, on, a global security, will credit the applicable direct participants’ accounts with payments in amounts proportionate to their respective beneficial interests in the principal amount of the global security as shown on the records of DTC. We also expect that payments by participants to owners of beneficial interests in the global security held through such participants will be governed by standing instructions and customary practices as is now the case with securities held for accounts for customers registered in “street name”; those payments will be the responsibility of such participants. Neither we, the trustee (in any of its capacities) nor any agent of ours or of the trustee will have any responsibility or liability for any aspect of the records relating to, or payments made on account of, beneficial interests in any global security or for maintaining, supervising or reviewing any records relating to such beneficial interests or for any other aspect of the relationship between DTC and its participants or the relationship between such participants and the owners of beneficial interests in the global securities.

Unless and until it is exchanged in whole or in part for certificated securities under the limited circumstances described below, a global security may not be transferred except as a whole by DTC to a nominee of DTC or by a nominee of DTC to DTC or another nominee of DTC or by DTC or any such nominee to a successor Depositary or a nominee of such successor Depositary. Transfers between participants in DTC will be effected in the ordinary way in accordance with DTC rules.

The indenture provides that the global securities will be exchanged for debt securities in certificated form only in the following limited circumstances:

Any global security that is exchanged for certificated securities as provided above will be exchanged for an equal aggregate principal amount of certificated securities, in authorized denominations and registered in such names as the Depositary instructs the trustee. It is expected that such instructions will be based upon directions received by the Depositary from participants with respect to ownership of beneficial interests in global securities. In connection with any proposed exchange of a global security for a certificated security, there shall be provided to the trustee all information necessary to allow the trustee to comply with any applicable tax reporting obligations, including, without limitation, any cost basis reporting obligations under Section 6045 of the Code (as defined below). The trustee may conclusively rely on information provided to it and shall have no responsibility to verify or ensure the accuracy of such information.

Euroclear and Clearstream

You may hold interests in global securities through Clearstream Banking S.A., which we refer to, together with any successor in such capacity, as “Clearstream,” or Euroclear Bank SA/NV, as operator of the Euroclear

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System, which we refer to, together with any successor in such capacity, as “Euroclear,” either directly if you are a participant in Clearstream or Euroclear or indirectly through organizations which are participants in Clearstream or Euroclear. Clearstream and Euroclear will hold interests on behalf of their respective participants through customers’ securities accounts in the names of Clearstream and Euroclear, respectively, on the books of their respective U.S. depositaries, which in turn will hold such interests in customers’ securities accounts in such depositaries’ names on DTC’s books.

Clearstream and Euroclear are securities clearance systems in Europe. Clearstream and Euroclear hold securities for their respective participating organizations and facilitate the clearance and settlement of securities transactions between those participants through electronic book-entry changes in their accounts, thereby eliminating the need for physical movement of certificates.

Payments, deliveries, transfers, exchanges, notices and other matters relating to beneficial interests in global securities owned through Euroclear or Clearstream must comply with the rules and procedures of those systems. Transactions between participants in Euroclear or Clearstream, on one hand, and other participants in DTC, on the other hand, are also subject to DTC’s rules and procedures.

Investors will be able to make and receive through Euroclear and Clearstream payments, deliveries, transfers and other transactions involving any beneficial interests in global securities held through those systems only on days when those systems are open for business. Those systems may not be open for business on days when banks, brokers and other institutions are open for business in the United States.

Cross-market transfers between participants in DTC, on the one hand, and participants in Euroclear or Clearstream, on the other hand, will be effected through DTC in accordance with the DTC’s rules on behalf of Euroclear or Clearstream, as the case may be, by their respective U.S. depositaries; however, such cross-market transactions will require delivery of instructions to Euroclear or Clearstream, as the case may be, by the counterparty in such system in accordance with the rules and procedures and within the established deadlines (European time) of such system. Euroclear or Clearstream, as the case may be, will, if the transaction meets its settlement requirements, deliver instructions to its U.S. depositary to take action to effect final settlement on its behalf by delivering or receiving interests in the global securities through DTC, and making or receiving payment in accordance with normal procedures for same-day fund settlement. Participants in Euroclear or Clearstream may not deliver instructions directly to their respective U.S. depositaries.

Due to time zone differences, the securities accounts of a participant in Euroclear or Clearstream purchasing an interest in a global security from a direct participant in DTC will be credited, and any such crediting will be reported to the relevant participant in Euroclear or Clearstream, during the securities settlement processing day (which must be a business day for Euroclear or Clearstream) immediately following the settlement date of DTC. Cash received in Euroclear or Clearstream as a result of sales of interests in a global security by or through a participant in Euroclear or Clearstream to a direct participant in DTC will be received with value on the settlement date of DTC but will be available in the relevant Euroclear or Clearstream cash account only as of the business day for Euroclear or Clearstream following DTC’s settlement date.

Other

The information in this section of this prospectus supplement concerning DTC, Clearstream, Euroclear and their respective book-entry systems has been obtained from sources that we believe to be reliable, but we do not take responsibility for this information. This information has been provided solely as a matter of convenience. The rules and procedures of DTC, Clearstream and Euroclear are solely within the control of those organizations and could change at any time. Neither we nor the trustee nor any agent of ours or of the trustee has any control over those entities and none of us takes any responsibility for their activities. You are urged to contact DTC, Clearstream and Euroclear or their respective participants directly to discuss those matters. In addition, although

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we expect that DTC, Clearstream and Euroclear will perform the foregoing procedures, none of them is under any obligation to perform or continue to perform such procedures and such procedures may be discontinued at any time. Neither we nor the trustee (in any of its capacities) nor any agent of ours or of the trustee will have any responsibility for the performance or nonperformance by DTC, Clearstream and Euroclear or their respective participants of these or any other rules or procedures governing their respective operations.

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MATERIAL UNITED STATES FEDERAL INCOME TAX CONSIDERATIONS

The following discussion is a summary of the material United States federal income tax consequences relevant to the purchase, ownership and disposition of the notes, but does not purport to be a complete analysis of all potential tax effects. The discussion is based upon the Internal Revenue Code of 1986, as amended (the “Code”), United States Treasury Regulations issued thereunder, Internal Revenue Service (the “IRS”) rulings and pronouncements and judicial decisions now in effect, all of which are subject to change at any time. Any such change may be applied retroactively in a manner that could adversely affect a holder of the notes. This discussion does not address all of the United States federal income tax consequences that may be relevant to a holder in light of such holder’s particular circumstances or to holders subject to special rules, such as banks, financial institutions, United States expatriates, insurance companies, dealers in securities or currencies, traders in securities, accrual method taxpayers subject to special tax accounting rules as a result of their use of financial statements pursuant to Section 451(b) of the Code, partnerships or other pass-through entities, United States Holders (as defined below) whose functional currency is not the United States dollar, tax-exempt organizations, persons subject to the alternative minimum tax and persons holding the notes as part of a “straddle,” “hedge,” “conversion transaction” or other integrated transaction. In addition, this discussion is limited to persons purchasing the notes for cash at original issue and at their “issue price” within the meaning of Section 1273 of the Code (i.e., the first price at which a substantial amount of notes is sold to the public for cash (excluding sales to bond houses, brokers or similar persons or organizations acting in the capacity of underwriters, placement agents or wholesalers)). Moreover, the effect of any applicable state, local or foreign tax laws or of United States federal estate or gift tax laws is not discussed. The discussion deals only with notes held as “capital assets” within the meaning of Section 1221 of the Code (generally, property held for investment).

As used herein, “United States Holder” means a beneficial owner of the notes who or that is or is treated for United States federal income tax purposes as:

As used herein, “non -United States Holder” means a beneficial owner of the notes who is not a United States Holder or a partnership or other entity treated as a partnership for United States federal income tax purposes.

No rulings from the IRS have been or are expected to be sought with respect to the matters discussed below. There can be no assurance that the IRS will not take a different position concerning the tax consequences of the purchase, ownership or disposition of the notes or that any such position would not be sustained. If a partnership or other entity taxable as a partnership holds the notes, the tax treatment of a partner will generally depend on the status of the partner and the activities of the partnership. Partnerships holding notes and partners in such partnerships should consult their tax advisors as to the tax consequences of holding and disposing of notes.

Prospective investors should consult their own tax advisors with regard to the application of the tax consequences discussed below to their particular situations as well as the application of any state, local, foreign or other tax laws, including gift and estate tax laws, and any tax treaties.

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Effect of Certain Contingencies

In certain circumstances (see “Description of the Notes—Optional Redemption” and “Description of the Notes—Change of Control Offer”), we may be obligated to pay amounts in excess of stated interest or principal on the notes. We intend to take the position that the possibility of such payments should not cause the notes to be treated as contingent payment debt instruments. This position is based in part on assumptions regarding the likelihood, as of the date of issuance of the notes, that such additional payments will be paid. Assuming the position is respected, a holder generally would not be required to include any income in respect of the foregoing contingencies unless and until any of the contingencies occurred. Our position is binding on a holder unless the holder explicitly discloses on its United States federal income tax return that it is taking a contrary position. However, our position is not binding on the IRS, and if the IRS were to challenge our position, a holder might be required to accrue income on its notes in excess of stated interest, and to treat as ordinary income, rather than capital gain, any gain realized on the taxable disposition of a note before the resolution of the contingencies. The remainder of this discussion assumes that the notes will not be treated as contingent payment debt instruments. Holders are urged to consult their own tax advisors regarding the potential application of the contingent payment debt instrument rules to the notes and the consequences thereof.

United States Holders

Interest

Payments of interest on the notes generally will be taxable to a United States Holder as ordinary income at the time that such payments are received or accrued, in accordance with such United States Holder’s method of accounting for United States federal income tax purposes.

Sale or Other Taxable Disposition of the Notes

A United States Holder will generally recognize gain or loss on the sale, exchange, redemption, retirement or other taxable disposition of a note equal to the difference between the amount realized upon the disposition (less any portion allocable to any accrued and unpaid interest not previously included in gross income, which will be taxable as interest) and the United States Holder’s adjusted tax basis in the note. A United States Holder’s adjusted tax basis in a note generally will be the United States Holder’s cost of the note, decreased by any principal payments received by such holder. This gain or loss generally will be a capital gain or loss, and will be a long-term capital gain or loss if the United States Holder has held the note for more than one year. Otherwise, such gain or loss will be a short-term capital gain or loss. Long-term capital gains of non-corporate holders are currently subject to tax at a reduced rate. The deductibility of capital losses is subject to limitations.

Backup Withholding and Information Reporting

A United States Holder may be subject to backup withholding when such holder receives interest and principal payments on the notes or upon the proceeds received upon the sale or other disposition of such notes. Certain holders (including, among others, corporations and certain tax-exempt organizations) are generally not subject to backup withholding. A United States Holder will be subject to backup withholding if such holder is not otherwise exempt and such holder:

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Backup withholding is not an additional tax and United States Holders may use amounts withheld as a credit against their United States federal income tax liability or may claim a refund as long as they timely provide certain information to the IRS.

Information with respect to interest on the notes will be required to be furnished to United States Holders, other than to certain exempt United States Holders, and to the IRS. Information with respect to the proceeds received upon the sale or other disposition of the notes will be required to be furnished to United States Holders, other than to certain exempt United States Holders, and to the IRS by a broker or other securities intermediary through which the United States Holders hold their notes.

Net Investment Income Tax

Certain United States Holders who are individuals, estates or trusts are subject to a 3.8% tax on all or a portion of their “net investment income”, which includes all or a portion of their interest income and gains from the sale or other disposition of a note. United States Holders should consult their tax advisors regarding the effect, if any, of the net investment income tax on their ownership or disposition of a note.

Non-United States Holders

Interest

Subject to the discussion below under “—Backup Withholding and Information Reporting” and “—Foreign Account Tax Compliance Act Withholding”, interest paid to a non-United States Holder will not be subject to United States federal withholding tax of 30% (or, if applicable, a lower treaty rate) provided that:

Even if the above conditions are not met, a non-United States Holder may be entitled to a reduction in or an exemption from withholding tax on interest under a tax treaty between the United States and the non-United States Holder’s country of residence. To claim such a reduction or exemption, a non-United States Holder must generally complete IRS Form W-8BEN or IRS Form W-8BEN-E (or other applicable form) and claim this reduction or exemption on the form. A non-United States Holder generally will also be exempt from withholding tax on interest if such interest is effectively connected with such holder’s conduct of a United States trade or business (as described below) and the holder provides us or the paying agent with an IRS Form W-8ECI.

The certification requirements described above may require a non-United States Holder that claims the benefit of an income tax treaty to also provide its United States TIN. Special certification requirements apply to intermediaries. Prospective investors should consult their tax advisors regarding the certification requirements for non-United States persons.

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Sale or Other Taxable Disposition of the Notes

Subject to the discussion below under “—Backup Withholding and Information Reporting”, a non-United States Holder will generally not be subject to United States federal income tax or withholding tax on gain recognized on the sale, exchange, redemption, retirement or other taxable disposition of a note that is not effectively connected with a United States trade or business of the non-United States Holder. However, a non-United States Holder may be subject to tax on such gain if such holder is an individual who was present in the United States for 183 days or more in the taxable year of the disposition and certain other conditions are met, in which case such holder may have to pay a United States federal income tax of 30% (or, if applicable, a lower treaty rate) on such gain. Such a holder is urged to consult his or her own tax advisor regarding the United States tax consequences of the sale or other disposition of notes.

United States Trade or Business

If interest or gain from a disposition of the notes is effectively connected with a non-United States Holder’s conduct of a United States trade or business or, if an income tax treaty applies, the non-United States Holder maintains a United States “permanent establishment” or fixed base to which the interest or gain is attributable, the non-United States Holder generally will be subject to United States federal income tax on the interest or gain on a net basis in the same manner as if it were a United States Holder. If interest with respect to the notes is taxable on a net basis, the 30% withholding tax described above will not apply (assuming an appropriate certification is provided). A foreign corporation that is a holder of a note also may be subject to a branch profits tax equal to 30% of its effectively connected earnings and profits for the taxable year, subject to certain adjustments, unless it qualifies for a lower rate under an applicable income tax treaty. For this purpose, interest on a note or gain recognized on the disposition of a note will be included in effectively connected earnings and profits if the interest or gain is effectively connected with the conduct by the foreign corporation of a trade or business in the United States. Holders to whom this paragraph may apply should consult their own tax advisors with respect to other United States tax consequences of the ownership and disposition of notes.

Backup Withholding and Information Reporting

Backup withholding will not apply to payments of principal or interest made by us or the paying agent, in our capacity or the paying agent’s capacity as such, to a non-United States Holder of a note if the holder meets the identification and certification requirements discussed above under “Non -United States Holders—Interest” for exemption from United States federal withholding tax or otherwise establishes an exemption. However, we must report annually to the IRS and to each non-United States Holder any interest that is paid to the non-United States Holder. Copies of these information returns also may be made available to the tax authorities of the country in which the non-United States Holder resides under the provisions of various treaties or agreements for the exchange of information. Payments of the proceeds from a disposition by a non-United States Holder of a note made to or through a foreign office of a broker will generally not be subject to information reporting or backup withholding, except that information reporting (but generally not backup withholding) may apply to those payments if the broker is:

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Payment of the proceeds from a disposition by a non-United States Holder of a note made to or through the United States office of a broker is generally subject to information reporting and backup withholding unless the holder or beneficial owner establishes an exemption from information reporting and backup withholding.

Non-United States Holders should consult their own tax advisors regarding application of withholding and backup withholding in their particular circumstance and the availability of and procedure for obtaining an exemption from withholding, information reporting and backup withholding. Backup withholding is not an additional tax and taxpayers may use amounts withheld as a credit against their United States federal income tax liability or may claim a refund as long as they timely provide certain information to the IRS.

Foreign Account Tax Compliance Act Withholding

Under the Foreign Account Tax Compliance Act (“FATCA”) and additional guidance issued by the IRS, a United States federal withholding tax of 30% generally will apply to interest on a debt obligation paid to (i) a foreign financial institution (as a beneficial owner or as an intermediary), unless such institution enters into an agreement with the United States government to collect and provide to the United States tax authorities substantial information regarding United States account holders of such institution (which would include certain equity and debt holders of such institution, as well as certain account holders that are foreign entities with United States owners), or (ii) a foreign entity that is not a financial institution (as a beneficial owner or as an intermediary), unless such entity provides the withholding agent with a certification identifying the substantial United States owners of the entity, which generally includes any United States person who directly or indirectly owns more than 10% of the entity, and meets certain other requirements. We will not pay any additional amounts to “gross up” payments to holders as a result of any withholding or deduction for such taxes. Non-United States Holders are encouraged to consult with their tax advisors regarding the possible implications of the FATCA withholding rules on their investment in the notes.

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UNDERWRITING

Subject to the terms and conditions in the underwriting agreement, dated as of the date of this prospectus supplement, among us and Wells Fargo Securities, LLC, BofA Securities, Inc. and J.P. Morgan Securities LLC. as representatives of the underwriters named below, we have agreed to sell to each underwriter, and each underwriter has, severally and not jointly, agreed to purchase from us, the principal amount of notes set forth opposite its name in the table below:

The underwriters are offering the notes subject to their acceptance of the notes from us and subject to prior sale. The underwriting agreement provides that the obligations of the several underwriters to pay for and accept delivery of the notes offered by this prospectus supplement are subject to certain conditions. The underwriters are obligated to take and pay for all of the notes offered by this prospectus supplement if any such notes are taken. If an underwriter defaults, the underwriting agreement provides that the purchase commitments of the non-defaulting underwriters may be increased or the underwriting agreement may be terminated.

The underwriters initially propose to offer the notes to the public at the public offering price that appears on the cover page of this prospectus supplement. The underwriters may offer the notes to selected dealers at the public offering price minus a concession of up to 0.350% of the principal amount of the notes. In addition, underwriters may allow, and those selected dealers may reallow, a concession of up to 0.250% of the principal amount of the notes to certain other dealers. After the initial offering, the underwriters may change the public offering prices and any other selling terms. The underwriters may offer and sell notes through certain of their affiliates.

The following table shows the underwriting discount that we will pay to the underwriters in connection with the offering of the notes:

In the underwriting agreement, we have agreed that:

No Sales of Similar Securities

We have agreed that we will not, during the period from the date of this prospectus supplement through and including the closing date of this offering, we will not, without the prior written consent of the representatives,

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offer, sell, contract to sell or otherwise dispose of any debt securities issued or guaranteed by us and having a tenor of more than one year.

New Issue of Notes

The notes are a new issue of securities with no established trading market. We do not intend to apply for the notes to be listed on any securities exchange or to arrange for the notes to be quoted on any quotation system. The underwriters have advised us that they intend to make a market in the notes, but they are not obligated to do so. The underwriters may discontinue any market making in the notes at any time at their sole discretion. Accordingly, we cannot assure you that a liquid trading market will develop for the notes, that you will be able to sell your notes at a particular time or that the prices you receive when you sell will be favorable.

Short Positions

In connection with the offering of the notes, the underwriters may engage in over-allotment, stabilizing transactions and syndicate-covering transactions. Over-allotment involves sales in excess of the offering size, which creates a short position for the underwriters. Stabilizing transactions involve bids to purchase the notes in the open market for the purpose of pegging, fixing or maintaining the prices of the notes. Syndicate-covering transactions involve purchases of the notes in the open market after the distribution has been completed in order to cover short positions. Stabilizing transactions and syndicate-covering transactions may cause the prices of the notes to be higher than they would otherwise be in the absence of those transactions. If the underwriters engage in stabilizing or syndicate-covering transactions, they may discontinue them at any time.

Other Relationships

Each of the underwriters and their respective affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, principal investment, hedging, financing and brokerage activities. In the ordinary course of their respective businesses, the underwriters and their respective affiliates have engaged, or may in the future engage, in commercial banking or investment banking transactions with us and our affiliates. In addition, the underwriters or their affiliates are lenders under our revolving credit facility and term credit facility.

In addition, in the ordinary course of their business activities, the underwriters and their affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers. Such investments and securities activities may involve securities and/or instruments of ours or our affiliates. If any of the underwriters or their affiliates have a lending relationship with us, certain of those underwriters or their affiliates routinely hedge, and certain other of those underwriters or their affiliates may hedge, their credit exposure to us consistent with their customary risk management policies. Typically, these underwriters and their affiliates would hedge such exposure by entering into transactions which consist of either the purchase of credit default swaps or the creation of short positions in our securities, including potentially the notes offered hereby. Any credit default swaps or such short positions could adversely affect future trading prices of the notes offered hereby. The underwriters and their affiliates may also make investment recommendations and/or publish or express independent research views in respect of such securities or financial instruments and may hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

Extended Settlement

It is expected that delivery of the notes will be made against payment therefor on or about August 21, 2024, which is the tenth business day following the date hereof (such settlement cycle being referred to as “T+10”). Pursuant to Rule 15c6-1 under the Exchange Act, trades in the secondary market generally are required to settle in one business day unless the parties to any such trade expressly agree otherwise. Accordingly, purchasers who

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wish to trade the notes prior to the date that is more than one business day preceding the settlement date will be required, by virtue of the fact that the notes initially will settle in T+10, to specify an alternate settlement cycle at the time of any such trade to prevent a failed settlement and should consult their own advisors.

Selling Restrictions

Australia

No placement document, prospectus, product disclosure statement or other disclosure document (including as defined in the Corporations Act 2001 (Cth) (“Corporations Act”)) has been or will be lodged with the Australian Securities and Investments Commission (“ASIC”) or any other governmental agency, in relation to the offering. This prospectus supplement and the accompanying prospectus do not constitute a prospectus, product disclosure statement or other disclosure document for the purposes of the Corporations Act, and does not purport to include the information required for a prospectus, product disclosure statement or other disclosure document under the Corporations Act. No action has been taken which would permit an offering of the notes in circumstances that would require disclosure under Parts 6D.2 or 7.9 of the Corporations Act.

The notes may not be offered for sale, nor may application for the sale or purchase or any notes be invited in Australia (including an offer or invitation which is received by a person in Australia) and neither this prospectus supplement, the accompanying prospectus nor any other offering material or advertisement relating to the notes may be distributed or published in Australia unless, in each case:

Canada

The notes may be sold only to purchasers purchasing, or deemed to be purchasing, as principal that are accredited investors, as defined in National Instrument 45-106 Prospectus Exemptions or subsection 73.3(1) of the Securities Act (Ontario), and are permitted clients, as defined in National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations. Any resale of the notes must be made in accordance with an exemption from, or in a transaction not subject to, the prospectus requirements of applicable securities laws.

Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if this prospectus (including any amendment thereto) contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser’s province or territory. The purchaser should refer to any applicable provisions of the securities legislation of the purchaser’s province or territory for particulars of these rights or consult with a legal advisor.

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Pursuant to section 3A.3 (or, in the case of securities issued or guaranteed by the government of a non-Canadian jurisdiction, section 3A.4) of National Instrument 33-105 Underwriting Conflicts (NI 33-105), the underwriters are not required to comply with the disclosure requirements of NI 33-105 regarding underwriter conflicts of interest in connection with this offering.

The Dubai International Financial Centre

This prospectus supplement and the accompanying prospectus relate to an Exempt Offer in accordance with the Markets Law, Dubai International Financial Centre (“DIFC”) Law No. 1 of 2012, as amended. This prospectus supplement and the accompanying prospectus are intended for distribution only to persons of a type specified in the Markets Law, DIFC Law No. 1 of 2012, as amended. It must not be delivered to, or relied on by, any other person. The Dubai Financial Services Authority (“DFSA”) has no responsibility for reviewing or verifying any documents in connection with Exempt Offers. The DFSA has not approved this prospectus supplement and the accompanying prospectus nor taken steps to verify the information set forth herein and has no responsibility for this prospectus supplement. The securities to which this prospectus supplement and the accompanying prospectus relate may be illiquid and/or subject to restrictions on their resale. Prospective purchasers of the securities offered should conduct their own due diligence on the securities. If you do not understand the contents of this prospectus supplement and the accompanying prospectus you should consult an authorized financial advisor.

In relation to its use in the DIFC, this prospectus supplement and the accompanying prospectus are strictly private and confidential and is being distributed to a limited number of investors and must not be provided to any person other than the original recipient, and may not be reproduced or used for any other purpose. The interests in the securities may not be offered or sold directly or indirectly to the public in the DIFC.

European Economic Area

Prohibition of Sales to EEA Investors

Each Manager has represented and agreed that it has not offered, sold or otherwise made available and will not offer, sell or otherwise make available any notes to any retail investor in the European Economic Area. For the purposes of this provision:

PROHIBITION OF SALES TO EEA RETAIL INVESTORS—The notes are not intended to be offered, sold or otherwise made available to and should not be offered, sold or otherwise made available to any retail investor in the European Economic Area. For these purposes, a retail investor means a person who is one (or more) of: (i) a retail client as defined in point (11) of Article 4(1) of Directive 2014/65/EU (as amended, “MiFID II”); (ii) a customer within the meaning of Directive (EU) 2016/97 (as amended or superseded, the “Insurance Distribution Directive”), where that customer would not qualify as a professional client as defined in point

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(10) of Article 4(1) of MiFID II; or (iii) not a qualified investor as defined in Regulation (EU) 2017/1129 (as amended or superseded, the “Prospectus Regulation”). Consequently no key information document required by Regulation (EU) No 1286/2014 (as amended, the “PRIIPs Regulation”) for offering or selling the notes or otherwise making them available to retail investors in the European Economic Area has been prepared and therefore offering or selling the notes or otherwise making them available to any retail investor in the European Economic Area may be unlawful under the PRIIPs Regulation.

Hong Kong

Each underwriter (i) has not offered or sold and will not offer or sell in Hong Kong, by means of any document, any notes other than (a) to “professional investors” as defined in the Securities and Futures Ordinance (Cap. 571 of the laws of Hong Kong) (the “SFO”) and any rules made thereunder; or (b) in other circumstances which do not result in the document being a “prospectus” as defined in the Companies (Winding Up and Miscellaneous Provisions) Ordinance (Cap. 32 of the Laws of Hong Kong) (the “CO”) or which do not constitute an offer to the public within the meaning of the CO; and (ii) has not issued or had in its possession for the purposes of issue, and will not issue or have in its possession for the purposes of issue, whether in Hong Kong or elsewhere, any advertisement, invitation or document relating to the notes, which is directed at, or the contents of which are likely to be accessed or read by, the public of Hong Kong (except if permitted to do so under the securities laws of Hong Kong) other than with respect to the notes which are or are intended to be disposed of only to persons outside Hong Kong or only to “professional investors” as defined in the SFO and any rules made thereunder.

Japan

The notes have not been and will not be registered pursuant to Article 4, Paragraph 1 of the Financial Instruments and Exchange Act. Accordingly, none of the notes nor any interest therein may be offered or sold, directly or indirectly, in Japan or to, or for the benefit of, any “resident” of Japan (which term as used herein means any person resident in Japan, including any corporation or other entity organized under the laws of Japan), or to others for re-offering or resale, directly or indirectly, in Japan or to or for the benefit of a resident of Japan, except pursuant to an exemption from the registration requirements of, and otherwise in compliance with, the Financial Instruments and Exchange Act and any other applicable laws, regulations and ministerial guidelines of Japan in effect at the relevant time.

Singapore

Each underwriter has acknowledged that this prospectus supplement and the accompanying prospectus have not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, each underwriter has represented, warranted and agreed that it has not offered or sold any notes or caused the notes to be made the subject of an invitation for subscription or purchase and will not offer or sell any notes or cause the notes to be made the subject of an invitation for subscription or purchase, and has not circulated or distributed, nor will it circulate or distribute, this prospectus supplement, the accompanying prospectus or any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the notes, whether directly or indirectly, to any person in Singapore other than:

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Switzerland

This prospectus supplement and the accompanying prospectus do not constitute an offer to the public or a solicitation to purchase or invest in any notes. The notes may not be publicly offered, sold or advertised, directly or indirectly, in, into or from Switzerland within the meaning of the Swiss Financial Services Act (“FinSA”) and no application has or will be made to admit the notes to trading on any trading venue (exchange or multilateral trading facility) in Switzerland. Neither this prospectus supplement, the accompanying prospectus nor any other offering or marketing material relating to the notes constitutes a prospectus pursuant to the FinSA, and neither this prospectus supplement, the accompanying prospectus nor any other offering or marketing material relating to the notes may be publicly distributed or otherwise made publicly available in Switzerland.

Taiwan

The notes have not been, and will not be registered, with the Financial Supervisory Commission of Taiwan, the Republic of China (“Taiwan”) pursuant to relevant securities laws and regulations and may not be sold, issued or offered within Taiwan through a public offering or in circumstances which constitutes an offer within the meaning of the Securities and Exchange Act of Taiwan that requires a registration or approval of the Financial Supervisory Commission of Taiwan. No person or entity in Taiwan has been authorized to offer, sell, give advice regarding or otherwise intermediate the offering and sale of the notes in Taiwan.

United Arab Emirates

The notes have not been, and are not being, publicly offered, sold, promoted or advertised in the United Arab Emirates (including the Dubai International Financial Centre) other than in compliance with the laws of the United Arab Emirates (and the Dubai International Financial Centre) governing the issue, offering and sale of securities. Further, this prospectus does not constitute a public offer of securities in the United Arab Emirates (including the Dubai International Financial Centre) and is not intended to be a public offer. This prospectus has not been approved by or filed with the Central Bank of the United Arab Emirates, the Securities and Commodities Authority, Financial Services Regulatory Authority or the Dubai Financial Services Authority.

United Kingdom

Prohibition of Sales to UK Retail Investors

Each Manager has represented and agreed that it has not offered, sold or otherwise made available and will not offer, sell or otherwise make available any notes to any retail investor in the United Kingdom. For the purposes of this provision:

(a) the expression “retail investor” means a person who is one (or more) of the following:

(b) the expression “offer” includes the communication in any form and by any means of sufficient information on the terms of the offer and the notes to be offered so as to enable an investor to decide to purchase or subscribe for the notes.

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PROHIBITION OF SALES TO UK RETAIL INVESTORS—The notes are not intended to be offered, sold or otherwise made available to and should not be offered, sold or otherwise made available to any retail investor in the United Kingdom (“UK”). For these purposes, a retail investor means a person who is one (or more) of: (i) a retail client, as defined in point (8) of Article 2 of Regulation (EU) No 2017/565 as it forms part of domestic law by virtue of the European Union (Withdrawal) Act 2018 (“EUWA”); (ii) a customer within the meaning of the provisions of the FSMA and any rules or regulations made under the FSMA to implement Directive (EU) 2016/97, where that customer would not qualify as a professional client, as defined in point (8) of Article 2(1) of Regulation (EU) No 600/2014 as it forms part of domestic law by virtue of the EUWA; or (iii) not a qualified investor as defined in Article 2 of Regulation (EU) 2017/1129 as it forms part of domestic law by virtue of the EUWA. Consequently no key information document required by Regulation (EU) No 1286/2014 as it forms part of domestic law by virtue of the EUWA (the “UK PRIIPs Regulation”) for offering or selling the notes or otherwise making them available to retail investors in the UK has been prepared and therefore offering or selling the notes or otherwise making them available to any retail investor in the UK may be unlawful under the UK PRIIPs Regulation.

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LEGAL MATTERS

Certain legal matters relating to the notes will be passed upon for us by Sidley Austin LLP, New York, New York, and for the underwriters by Davis Polk & Wardwell LLP, New York, New York.

EXPERTS

The financial statements of IDEX Corporation as of December 31, 2023 and 2022, and for each of the three years in the period ended December 31, 2023, incorporated by reference in this prospectus supplement, and the effectiveness of IDEX Corporation’s internal control over financial reporting have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports. Such financial statements are incorporated by reference in reliance upon the reports of such firm given upon their authority as experts in accounting and auditing.

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PROSPECTUS

IDEX CORPORATION

Debt Securities

We intend to offer from time to time our debt securities. We may sell these securities in one or more offerings at prices and on other terms to be determined at the time of offering.

We will provide the specific terms of the securities to be offered in one or more supplements to this prospectus. You should read this prospectus and the applicable prospectus supplement carefully before you invest in our securities. This prospectus may not be used to offer and sell our securities unless accompanied by a prospectus supplement describing the method and terms of the offering of those offered securities.

We may offer our debt securities through agents, underwriters or dealers or directly to investors. Each prospectus supplement will provide the amount, price and terms of the plan of distribution relating to the debt securities to be sold pursuant to such prospectus supplement. We will set forth the names of any underwriters or agents in the accompanying prospectus supplement, as well as the net proceeds we expect to receive from such sale. In addition, the underwriters, if any, may over-allot a portion of the securities.

Investing in our debt securities involves risks. See “Risk Factors” beginning on page 2 of this prospectus, in the documents that are incorporated by reference into this prospectus and in the applicable prospectus supplement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is February 23, 2024.

TABLE OF CONTENTS

i

ABOUT THIS PROSPECTUS

This prospectus is part of an automatic shelf registration statement that we filed with the Securities and Exchange Commission (the “SEC”) as a “well-known seasoned issuer” as defined in Rule 405 under the Securities Act of 1933, as amended (the “Securities Act”). We may offer the securities described in this prospectus from time to time in one or more offerings. This prospectus only provides you with a general description of the securities to be offered. Each time we sell securities pursuant to this prospectus, we will describe in a prospectus supplement, which will be delivered with this prospectus, specific information about the offering and the terms of the particular securities to be offered. The applicable prospectus supplement and any related free writing prospectus may also add, update or change the information contained in this prospectus. If there is any inconsistency between the information in this prospectus and any applicable prospectus supplement, you should rely on the information in the applicable prospectus supplement. You should carefully read both this prospectus, the applicable prospectus supplement and any related free writing prospectus, together with the additional information described under the heading “Where You Can Find More Information.”

The registration statement of which this prospectus is a part, including the exhibits to the registration statement, provides additional information about us and the securities. Wherever references are made in this prospectus to information that will be included in a prospectus supplement, to the extent permitted by applicable law, rules or regulations, we may instead include such information or add, update or change the information contained in this prospectus by means of a post-effective amendment to the registration statement of which this prospectus is a part, through filings we make with the SEC that are incorporated by reference into this prospectus or by any other method as may then be permitted under applicable law, rules or regulations. The registration statement, including the exhibits to the registration statement and any post-effective amendment thereto, can be obtained from the SEC, as described under the heading “Where You Can Find More Information.”

We are responsible for the information contained and incorporated by reference into this prospectus and any prospectus supplement we may authorize to be delivered to you. We have not authorized anyone to provide you with different information. We are not making offers to sell the securities in any jurisdiction in which an offer or solicitation is not authorized or in which the person making such offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make an offer or solicitation. You should not assume that the information contained in this prospectus or any prospectus supplement is accurate as of any date other than the date mentioned on its cover page and that any information we have incorporated by reference is accurate as of any date other than the date of the document incorporated by reference. Our business, financial condition, results of operations and prospects may have changed since such dates.

Unless otherwise indicated or unless the context requires otherwise, all references in this prospectus supplement to the terms “we,” “us,” “our,” “the Company” or “IDEX” or other similar terms mean IDEX Corporation and its direct and indirect subsidiaries on a consolidated basis.

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FORWARD-LOOKING STATEMENTS

This prospectus, the accompanying prospectus supplement (including the information incorporated by reference in this prospectus and the accompanying prospectus supplement) and any free writing prospectus with respect to this offering filed by us with the SEC contain “forward-looking” statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended. These statements are indicated by words or phrases such as “anticipates,” “estimates,” “plans,” “guidance,” “expects,” “projects,” “forecasts,” “should,” “could,” “will,” “management believes,” “the Company believes,” “the Company intends” and similar words or phrases. These statements are subject to inherent uncertainties and risks that could cause actual results to differ materially from those anticipated at the date of this prospectus. The risks and uncertainties include, but are not limited to, the following: levels of industrial activity and economic conditions in the United States and other countries around the world, including uncertainties in the financial markets and adverse developments affecting the financial services industry; pricing pressures, including inflation and rising interest rates, and other competitive factors and levels of capital spending in certain industries, all of which could have a material impact on our order rates and results; the impact of catastrophic weather events, natural disasters and public health threats; economic and political consequences resulting from terrorist attacks and wars, which could have an adverse impact on our business by creating disruptions in the global supply chain and by potentially having an adverse impact on the global economy; our ability to make acquisitions and to integrate and operate acquired businesses on a profitable basis; cybersecurity incidents; the relationship of the United States dollar to other currencies and its impact on pricing and cost competitiveness; political and economic conditions in foreign countries in which we operate; developments with respect to trade policy and tariffs; interest rates; capacity utilization and the effect this has on costs; labor markets; supply chain conditions; market conditions and material costs; risks related to environmental, social and corporate governance issues, including those related to climate change and sustainability; and developments with respect to contingencies, such as litigation and environmental matters and the other risk factors identified under the heading “Risk Factors” in this prospectus and under the heading “Risk Factors” in our Annual Report on Form 10-K for the fiscal year ended December 31, 2023, any subsequently filed Quarterly Reports on Form 10-Q and the other reports that we file with the SEC, each of which is incorporated by reference herein. See “Information Incorporated by Reference” below. Additional factors that may cause risks and uncertainties include those discussed in the sections entitled “Business” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” in our Annual Report on Form 10-K for the fiscal year ended December 31, 2023 and the risk factors and other information discussed in other documents that are incorporated or deemed to be incorporated by reference in this prospectus and the accompanying prospectus supplement. The forward-looking statements included in this prospectus, the accompanying prospectus supplement, any document incorporated by reference herein or therein or any free writing prospectus are only made as of the date on which it is made, and management undertakes no obligation to publicly update them to reflect subsequent events or circumstances, except as may be required by law. Investors are cautioned not to rely unduly on forward-looking statements when evaluating the information presented in this prospectus, the accompanying prospectus supplement, any document incorporated by reference herein or therein or any free writing prospectus.

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THE COMPANY

We are an applied solutions provider specializing in the manufacturing of fluid and metering technologies, health and science technologies and fire, safety and other diversified products built to customers’ specifications. Our products are sold in niche markets across a wide range of industries throughout the world. Our products and services include positive displacement pumps, valves, small volume provers, flow meters, injectors and other fluid-handling pump modules and systems, flow monitoring and other services, precision fluidics, powder and liquid processing technologies, drying systems, micro-precision components, pneumatic components and sealing solutions, high performance molded and extruded sealing components, custom mechanical and shaft seals, engineered hygienic mixers and valves, biocompatible medical devices and implantables, air compressors and blowers, optical components and coatings, laboratory and commercial equipment, precision photonic solutions, firefighting pumps, valves and controls, rescue tools, lifting bags and other components and systems for the fire and rescue industry, engineered stainless steel banding and clamping devices and precision equipment for dispensing, metering and mixing colorants and paints. These products and services are grouped into three reportable segments: Fluid & Metering Technologies, Health & Science Technologies and Fire & Safety/Diversified Products. Substantially all of IDEX Corporation’s business activities are carried out through wholly-owned subsidiaries.

IDEX Corporation was incorporated as a Delaware corporation on September 24, 1987. Our principal executive offices are located at 3100 Sanders Road, Suite 301, Northbrook, Illinois 60062. Our telephone number at that location is (847) 498-7070.

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RISK FACTORS

Investing in our securities involves risks. You should carefully consider the risk factors discussed under the heading “Forward-Looking Statements” provided at the beginning of this prospectus, the risks described under “Risk Factors” in our most recent annual report on Form 10-K and in our most recent quarterly reports on Form 10-Q, including any amendments thereto reflected in subsequent filings with the SEC, as well as the other information included or incorporated by reference in this prospectus, before making an investment decision. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also adversely affect our business or financial performance. Our business, financial condition or results of operations could be materially adversely affected by any of these risks. The market or trading prices of our securities could decline due to any of these risks or other factors, and you may lose all or part of your investment.

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USE OF PROCEEDS

Unless the applicable prospectus supplement indicates otherwise, we intend to use the net proceeds from the sale of the debt securities offered by this prospectus through any applicable prospectus supplement for general corporate purposes, which may include working capital, acquisitions, capital expenditures and repayment of existing indebtedness.

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DESCRIPTION OF DEBT SECURITIES

The following description sets forth certain general terms and provisions of the debt securities that we may issue. We will set forth the particular terms of the debt securities we offer in a prospectus supplement and the extent, if any, to which the following general terms and provisions will apply to particular debt securities.

The debt securities will be issued under that certain indenture, dated as of December 6, 2010 (as amended and supplemented from time to time, the “Indenture”), by and between us and Computershare Trust Company, National Association (as successor to Wells Fargo Bank, National Association), as trustee (the “Trustee”). The Indenture, and any supplemental indentures thereto, will be subject to, and governed by, the Trust Indenture Act of 1939, as amended. The following description of general terms and provisions relating to the debt securities and the Indenture under which the debt securities will be issued is a summary only and therefore is not complete and is subject to, and qualified in its entirety by reference to, the terms and provisions of the Indenture. The particular terms of the debt securities offered by any prospectus supplement and the extent, if any, to which these general provisions may apply to the debt securities will be described in the applicable prospectus supplement. The Indenture has been filed with the SEC and is incorporated by reference as an exhibit to the registration statement of which this prospectus forms a part, and you should read the Indenture for provisions that may be important to you. For more information on how you can obtain a copy of the Indenture, see “Where You Can Find More Information.”

Capitalized terms used in this section and not defined herein have the meanings specified in the Indenture.

Unless otherwise specified in a prospectus supplement, the debt securities will be our direct, unsecured obligations and will rank equally with all of our other unsecured indebtedness.

The prospectus supplement relating to any series of debt securities that we may offer will contain the specific terms of the debt securities. These terms may include the following:

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General

We can issue an unlimited amount of debt securities under the Indenture that may be in one or more series. We may sell the debt securities, including original issue discount securities, at par or at a substantial discount below their stated principal amount. Unless we inform you otherwise in a prospectus supplement, we may issue additional debt securities of a particular series without the consent of the holders of the debt securities of such series outstanding at the time of issuance provided that the debt securities of such series and such additional securities would be fungible with each other for United States federal income tax purposes. Any such additional debt securities, together with all other outstanding debt securities of that series, will constitute a single series of securities under the Indenture. In addition, we will describe in the applicable prospectus supplement, material United States federal tax considerations and any other special considerations for any debt securities we sell which are denominated in a currency or currency unit other than United States dollars. Any taxes withheld or deducted from payments in respect of the debt securities and paid to the relevant tax authority shall be deemed to have been paid to the applicable holder. Unless we inform you otherwise in the applicable prospectus supplement, the debt securities will not be listed on any securities exchange.

We expect most debt securities to be issued in fully registered form without coupons and in denominations of $2,000 and any integral multiples of $1,000 thereof. Subject to the limitations provided in the Indenture and in the applicable prospectus supplement, debt securities that are issued in registered form may be transferred or exchanged at the corporate office of the Trustee or the principal corporate trust office of the Trustee, without the payment of any service charge, other than any tax or other governmental charge payable in connection therewith.

Global Securities

Unless we inform you otherwise in the applicable prospectus supplement, the debt securities of a series may be issued in whole or in part in the form of one or more global securities that will be deposited with, or on behalf of, a depositary identified in the applicable prospectus supplement. Global securities will be issued in registered form and in either temporary or definitive form. Unless and until it is exchanged in whole or in part for the individual debt securities, a global security may not be transferred except as a whole by the depositary for such global security to a nominee of such depositary or by a nominee of such depositary to such depositary or another nominee of such depositary or by such depositary or any such nominee to a successor of such depositary or a

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nominee of such successor. The specific terms of the depositary arrangement with respect to any debt securities of a series and the rights of and limitations upon owners of beneficial interests in a global security will be described in the applicable prospectus supplement.

Certain Terms of the Debt Securities

Covenants

Unless otherwise indicated in a prospectus supplement, the debt securities will not contain any financial or restrictive covenants, including covenants restricting either us or any of our subsidiaries from incurring, issuing, assuming or guarantying any indebtedness secured by a lien on any of our or our subsidiaries’ property or capital stock, or restricting either us or any of our subsidiaries from entering into sale and leaseback transactions.

Consolidation, Merger, Sale or Conveyance

Unless otherwise indicated in a prospectus supplement, we will not consolidate with or merge with any other Person, or sell, convey, transfer or lease all or substantially all of our assets to any Person, unless:

This covenant will not apply to any sale, assignment, transfer, conveyance, lease or other disposition of assets solely between or among us and our U.S. Subsidiaries.

In the event that we consolidate with or merge with another Person or sell substantially all of our assets to any other Person, the surviving entity (if other than us) will be substituted for us under the Indenture, and we will be discharged from all of our obligations under the Indenture.

Events of Default

An event of default for any series of debt securities is defined under the Indenture as being:

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Unless otherwise indicated in a prospectus supplement with respect to a particular series of debt securities, the default by us under any other debt, including any other series of debt securities, is not a default under the Indenture.

If an event of default other than an event of default specified in the last two bullet points above occurs with respect to a series of debt securities and is continuing under the Indenture, then, and in each and every such case, either the Trustee or the holders of not less than 25% in principal amount of such series then outstanding under the Indenture (each such series voting as a separate class) by written notice to us and to the Trustee, if such notice is given by the holders, may declare the principal amount of and accrued interest, if any, on such debt securities to be immediately due and payable.

If an event of default specified in the last two bullet points above occurs with respect to us and is continuing, then, and in each and every such case, the entire principal amount of, and accrued interest, if any, on each series of debt securities then outstanding shall ipso facto become to be immediately due and payable without any declaration or other act on the part of the Trustee or any holder.

Upon certain conditions, declarations of acceleration may be rescinded and annulled and past defaults may be waived by the holders of a majority in aggregate principal amount of all the debt securities of such series affected by the default, each series voting as a separate class (or, of all the debt securities, as the case may be, voting as a single class). Furthermore, subject to various provisions in the Indenture, the holders of at least a majority in aggregate principal amount of a series of debt securities, by notice to the Trustee, may waive an existing default or event of default with respect to such debt securities and its consequences, except a default in the payment of principal of or interest on such debt securities or in respect of a covenant or provision of the Indenture which cannot be modified or amended without the consent of the holders of each such debt security. Upon any such waiver, such default shall cease to exist, and any event of default with respect to such debt securities shall be deemed to have been cured, for every purpose of the Indenture; but no such waiver shall extend to any subsequent or other default or event of default or impair any right consequent thereto. For information as to the waiver of defaults, see “—Modification and Waiver.”

The holders of at least a majority in aggregate principal amount of a series of debt securities may direct the time, method and place of conducting any proceeding for any remedy available to the Trustee or exercising any trust or power conferred on the Trustee with respect to such debt securities. However, the Trustee may refuse to

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follow any direction that conflicts with law or the Indenture, that may involve the Trustee in personal liability, or that the Trustee determines in good faith may be unduly prejudicial to the rights of holders of such series of debt securities not joining in the giving of such direction and may take any other action it deems proper that is not inconsistent with any such direction received from holders of such series of debt securities. A holder may not pursue any remedy with respect to the Indenture or any series of debt securities unless:

These limitations, however, do not apply to the right of any holder of a debt security to receive payment of the principal of or interest, if any, on such debt security, or to bring suit for the enforcement of any such payment, on or after the due date for the debt securities, which right shall not be impaired or affected without the consent of the holder.

The Indenture requires certain of our officers to certify, on or before a fixed date in each year in which any debt security is outstanding, as to their knowledge of our compliance with all conditions and covenants under the Indenture.

Defeasance and Discharge

The term defeasance means we are discharged from some or all of our obligations under the Indenture. If we deposit in trust with the Trustee under the Indenture any combination of money or government securities in an amount sufficient to make payments on the debt securities of a series issued under the Indenture on the dates those payments are due, then, at our option:

If a series of debt securities is defeased, the holders of the debt securities of that series will not be entitled to the benefits of the Indenture, except for obligations to register the transfer or exchange of debt securities, replace stolen, lost or mutilated debt securities or maintain paying agencies and hold money for payment in trust.

Unless we inform you otherwise in the prospectus supplement, we will be required to deliver to the Trustee an opinion of counsel that the deposit and related defeasance would not cause the beneficial owners of the debt securities to recognize income, gain or loss for United States federal income tax purposes and that the beneficial owners would be subject to United States federal income tax on the same amounts, in the same manner and at the same times as would have been the case if the deposit and related defeasance had not occurred. If we elect legal defeasance, that opinion of counsel must be based upon a ruling from the United States Internal Revenue Service or a change in law to that effect.

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Satisfaction and Discharge

In addition, unless the terms of any series of debt securities provides otherwise, we may discharge our obligations with respect to a series of debt securities and the Indenture with respect to such series of debt securities when:

With respect to the first and second bullet points above, only our obligations to compensate and indemnify the Trustee and our right to recover unclaimed money held by the Trustee under the Indenture will survive. With respect to the third bullet point above, certain rights and obligations under the Indenture (such as our obligation to maintain an office or agency in respect of such debt securities, to have moneys held for payment in trust, to register the transfer or exchange of such debt securities, to deliver such debt securities for replacement or to be canceled, to compensate and indemnify the Trustee and to appoint a successor trustee, and our right to recover unclaimed money held by the Trustee) will survive until such debt securities are no longer outstanding. Thereafter, only our obligations to compensate and indemnify the Trustee and our right to recover unclaimed money held by the Trustee will survive.

Modification and Waiver

We and the Trustee may amend or supplement the Indenture or the debt securities without notice to or the consent of any holder:

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Other amendments and modifications of the Indenture or the debt securities issued may be made, and our compliance with any provision of the Indenture with respect to any series of debt securities may be waived, with the consent of the holders of not less than a majority of the aggregate principal amount of the debt securities of all series affected by the amendment or modification (voting as one class); provided, however, that each affected holder must consent to any modification, amendment or waiver that:

It shall not be necessary for the consent of the holders under the Indenture to approve the particular form of any proposed amendment, supplement or waiver, but it shall be sufficient if such consent approves the substance thereof. After an amendment, supplement or waiver under this section of the Indenture becomes effective, we will give to the holders affected thereby certain notice briefly describing the amendment, supplement or waiver.

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We will mail copies of supplemental indentures to holders upon request. Any failure to give such notice, or any defect therein, shall not, however, in any way impair or affect the validity of any such supplemental indenture or waiver.

No Personal Liability of Incorporators, Stockholders, Officers or Directors

The Indenture provides that no recourse shall be had under or upon any obligation, covenant or agreement of ours in the Indenture or any supplemental indenture, or in any of the debt securities or because of the creation of any indebtedness represented thereby, against any incorporator, stockholder, officer or director of ours or of any successor person thereof under any law, statute or constitutional provision or by the enforcement of any assessment or by any legal or equitable proceeding or otherwise. Each holder, by accepting the debt securities, waives and releases all such liability.

Concerning the Trustee

The Indenture provides that, except during the continuance of an event of default, the Trustee will not be liable, except for the performance of such duties as are specifically set forth in the Indenture. If an event of default has occurred and is continuing, the Trustee will exercise such rights and powers vested in it under the Indenture and will use the same degree of care and skill in their exercise as a prudent person would exercise under the circumstances in the conduct of such person’s own affairs.

Unclaimed Funds

All funds deposited with the Trustee or any paying agent for the payment of principal, interest, premium or additional amounts in respect of the debt securities that remain unclaimed for two years after the maturity date of such debt securities will be repaid to us upon our request. Thereafter, any right of any noteholder to such funds shall be enforceable only against us, and the Trustee and paying agents will have no liability therefor.

Governing Law

The Indenture and the debt securities will be governed by, and construed in accordance with, the internal laws of the State of New York.

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PLAN OF DISTRIBUTION

We may sell the offered debt securities:

We may distribute the debt securities from time to time in one or more transactions, at a fixed price or prices, which may be changed, or at market prices prevailing at the time of sale, at prices related to the prevailing market prices or at negotiated prices. In some cases, we or dealers acting with or on behalf of us may also purchase the debt securities and reoffer them to the public.

Underwriters, dealers and agents that participate in the distribution of the offered debt securities may be underwriters as defined in the Securities Act, and any discounts or commissions received by them from us and any profit on the resale of the offered debt securities by them may be treated as underwriting discounts and commissions under the Securities Act. We will identify any managing underwriter, other underwriters or agents, and describe their compensation and the terms of the transactions, in a prospectus supplement.

If we use underwriters in the sale, we will execute an underwriting agreement with the underwriters at the time we reach an agreement for the sale of the debt securities. The underwriters will acquire the debt securities for their own account. The underwriters may resell the debt securities in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. The obligations of the underwriters to purchase the debt securities will be subject to certain conditions. The underwriters will be obligated to purchase all of the debt securities offered if any of the debt securities are purchased. The underwriters may change from time to time any initial public offering price and any discount or concession allowed or re-allowed or paid to dealers.

We may sell the offered debt securities through agents designated by us. Unless otherwise indicated in the applicable prospectus supplement, any agents will agree to use their reasonable best efforts to solicit purchases for the period of their appointment.

If we use dealers in the sale, we will sell the debt securities to the dealer, as principal. The dealer will then sell the debt securities to the public at varying prices that the dealer will determine at the time it sells the debt securities.

We may sell the securities directly to institutional investors or others. The applicable prospectus supplement will describe the terms of any sale of securities we are offering to purchasers directly. Direct sales may be arranged by a broker-dealer or other financial intermediary.

Unless we inform you otherwise in the applicable prospectus supplement, the debt securities will not be listed on a national securities exchange or a foreign securities exchange. Each series of debt securities may be a new issue of securities with no established trading market. Underwriters and agents may, from time to time, purchase and sell the debt securities described in this prospectus and the relevant prospectus supplement in the secondary market, but are not obligated to do so. No assurance can be given that there will be a secondary market for the debt securities or liquidity in the secondary market if one develops. From time to time, underwriters and dealers may make a market in the debt securities.

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In connection with underwritten offerings of the offered debt securities and in accordance with applicable law and industry practice, the underwriters in certain circumstances are permitted to engage in certain transactions that stabilize the price of the debt securities. Such transactions consist of bids or purchases for the purpose of pegging, fixing or maintaining the price of the debt securities. If the underwriters create a short position in the debt securities in connection with the offering, i.e., if they sell more debt securities than are set forth on the cover page of the applicable prospectus supplement, the underwriters may reduce that short position by purchasing debt securities in the open market. The underwriters also may impose a penalty bid on certain underwriters. This means that if the underwriters purchase the debt securities in the open market to reduce the underwriters’ short position or to stabilize the price of the debt securities, they may reclaim the amount of the selling concession from the underwriters who sold those debt securities as part of the offering. In general, purchases of a debt security for the purpose of stabilization or to reduce a short position could cause the price of the debt security to be higher than it might be in the absence of such purchases.

The imposition of a penalty bid might also have an effect on the price of a debt security to the extent that it were to discourage resales of the debt security.

If we so specify in the applicable prospectus supplement, we may authorize underwriters, dealers or agents to solicit offers by institutions to purchase the securities pursuant to contracts providing for payment and delivery on future dates. Such contracts may be subject to conditions described in the applicable prospectus supplement.

If so provided in the applicable prospectus supplement, underwriters, dealers and agents will not be responsible for the validity or performance of any delayed delivery contracts. We will set forth in the prospectus supplement relating to the delayed delivery contracts the price to be paid for the securities, the commissions payable for solicitation of the delayed delivery contracts and the date in the future for delivery of the securities.

We may have agreements with the underwriters, dealers and agents to indemnify them against certain civil liabilities, including liabilities under the Securities Act, or to contribute with respect to payments which the underwriters, dealers or agents may be required to make. Underwriters, dealers and agents may engage in transactions with, or perform services for, us or our subsidiaries in the ordinary course of their businesses.

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LEGAL MATTERS

Certain legal matters relating to the debt securities will be passed upon for us by Sidley Austin LLP, New York, New York.

EXPERTS

The financial statements of IDEX Corporation incorporated by reference in this prospectus and the accompanying prospectus supplement, and the effectiveness of IDEX Corporation’s internal control over financial reporting have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports. Such financial statements are incorporated by reference in reliance upon the reports of such firm given their authority as experts in accounting and auditing.

WHERE YOU CAN FIND MORE INFORMATION

We are subject to the information reporting requirements of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and, in accordance with these requirements, we are required to file periodic reports and other information with the SEC. This prospectus is part of a registration statement that we filed with the SEC. The registration statement, including the attached exhibits, contains additional relevant information about us. The rules of the SEC allow us to omit from this prospectus and the accompanying prospectus supplement some of the information included in the registration statement. You will find additional information about us in the registration statement and the exhibits and schedules filed therewith and in our reports and other information incorporated by reference herein. The SEC filings are available at the website maintained by the SEC at http://www.sec.gov.

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INFORMATION INCORPORATED BY REFERENCE

The SEC allows us to “incorporate by reference” the information contained in documents we file with the SEC, which means that we can disclose important information to you by referring to those documents. The information incorporated by reference is an important part of this prospectus. Any statement contained in a document which is incorporated by reference into this prospectus is automatically updated and superseded if information contained in this prospectus, or information that we later file with the SEC, modifies or revises that statement. Any such statement so modified or revised shall not be deemed, except as so modified or revised, to constitute a part of this prospectus. We incorporate by reference the following documents we filed, excluding any information contained therein or attached as an exhibit thereto which has been furnished, but not filed, with the SEC:

Any documents we file pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this prospectus and prior to the termination of the offering of the debt securities to which this prospectus relates (in each case, other than any documents or information deemed to have been “furnished” and not “filed” in accordance with SEC rules) will automatically be deemed to be incorporated by reference into this prospectus and be deemed a part of this prospectus from the date of filing such documents.

The documents incorporated by reference into this prospectus are available from us at no cost upon your request. We will provide a copy of any and all of the information that is incorporated by reference into this prospectus to any person, without charge, upon written or oral request. If exhibits to the documents incorporated by reference into this prospectus are not themselves specifically incorporated by reference into this prospectus, then the exhibits will not be provided.

Requests for documents relating to us should be directed to:

Abhishek Khandelwal

Senior Vice President and Chief Financial Officer

IDEX Corporation

3100 Sanders Road

Suite 301

Northbrook, Illinois 60062

(847) 498-7070

We also maintain a website that is located at www.idexcorp.com. Information on or accessible through our website is not part of, or incorporated by reference into, this prospectus.

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IDEX CORPORATION

$500,000,000 4.950% Senior Notes due 2029

PROSPECTUS SUPPLEMENT

Joint Book-Running Managers

Wells Fargo Securities

BofA Securities

J.P. Morgan

PNC Capital Markets LLC

Senior Co-Managers

HSBC

Mizuho

Loop Capital Markets

Co-Managers

COMMERZBANK

Siebert Williams Shank

August 7, 2024