Amphenol (APH) 10-Q 26 Apr 24 2024 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2024	Apr. 23, 2024
Document and Entity Information
Entity Registrant Name	AMPHENOL CORPORATION
Entity Central Index Key	0000820313
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Mar. 31, 2024
Entity File Number	1-10879
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	22-2785165
Entity Address, Address Line One	358 Hall Avenue
Entity Address, City or Town	Wallingford
Entity Address, State or Province	CT
Entity Address, Postal Zip Code	06492
City Area Code	203
Local Phone Number	265-8900
Title of 12(b) Security	Class A Common Stock, $0.001 par value
Trading Symbol	APH
Security Exchange Name	NYSE
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		600,603,947
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Current Assets:
Cash and cash equivalents	$ 1,857.1	$ 1,475
Short-term investments	106.4	185.2
Total cash, cash equivalents and short-term investments	1,963.5	1,660.2
Accounts receivable, less allowance for doubtful accounts of $68.0 and $68.4, respectively	2,501.4	2,618.4
Inventories	2,152.9	2,167.1
Prepaid expenses and other current assets	423.9	389.6
Total current assets	7,041.7	6,835.3
Property, plant and equipment, less accumulated depreciation of $2,304.1 and $2,261.8, respectively	1,311.6	1,314.7
Goodwill	7,100.5	7,092.4
Other intangible assets, net	785.4	834.8
Other long-term assets	483.3	449.2
Total assets	16,722.5	16,526.4
Current Liabilities:
Accounts payable	1,264.7	1,350.9
Accrued salaries, wages and employee benefits	351.2	412.8
Accrued income taxes	150.9	166
Accrued dividends	132.1	131.7
Other accrued expenses	771.7	737.5
Current portion of long-term debt	752.5	353.8
Total current liabilities	3,423.1	3,152.7
Long-term debt, less current portion	3,556.9	3,983.5
Accrued pension and postretirement benefit obligations	142.1	143
Deferred income taxes	371	367
Other long-term liabilities	464.8	453.7
Total Liabilities	7,957.9	8,099.9
Redeemable noncontrolling interests	30.9	30.7
Equity:
Common stock	0.6	0.6
Additional paid-in capital	3,224.1	3,101.2
Retained earnings	6,163.5	5,921.1
Treasury stock, at cost	(103.8)	(142.8)
Accumulated other comprehensive loss	(602.9)	(533.6)
Total stockholders' equity attributable to Amphenol Corporation	8,681.5	8,346.5
Noncontrolling interests	52.2	49.3
Total equity	8,733.7	8,395.8
Total Liabilities, Redeemable Noncontrolling Interests and Equity	$ 16,722.5	$ 16,526.4

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Condensed Consolidated Balance Sheets
Allowance for doubtful accounts	$ 68	$ 68.4
Accumulated depreciation	$ 2,304.1	$ 2,261.8

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Condensed Consolidated Statements of Income
Net sales	$ 3,256.3	$ 2,974
Cost of sales	2,167.3	2,030.6
Gross profit	1,089	943.4
Acquisition-related expenses	0	5.4
Selling, general and administrative expenses	404.2	346.3
Operating income	684.8	591.7
Interest expense	(38.1)	(35.9)
Other income (expense), net	16	4.1
Income before income taxes	662.7	559.9
Provision for income taxes	(110.7)	(117.2)
Net income	552	442.7
Less: Net income attributable to noncontrolling interests	(3.3)	(3.5)
Net income attributable to Amphenol Corporation	$ 548.7	$ 439.2
Net income attributable to Amphenol Corporation per common share - Basic (in dollars per share)	$ 0.91	$ 0.74
Weighted average common shares outstanding - Basic (in shares)	600	595.1
Net income attributable to Amphenol Corporation per common share - Diluted (in dollars per share)	$ 0.87	$ 0.71
Weighted average common shares outstanding - Diluted (in shares)	627.9	619.9

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Condensed Consolidated Statements of Comprehensive Income
Net income	$ 552	$ 442.7
Total other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	(71.2)	42.5
Pension and postretirement benefit plan adjustment, net of tax of ($0.3) and ($0.2), respectively	0.9	0.7
Total other comprehensive income (loss), net of tax	(70.3)	43.2
Total comprehensive income	481.7	485.9
Less: Comprehensive income attributable to noncontrolling interests	(2.3)	(4.3)
Comprehensive income attributable to Amphenol Corporation	$ 479.4	$ 481.6

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Condensed Consolidated Statements of Comprehensive Income
Pension and postretirement benefit plan adjustment, tax	$ (0.3)	$ (0.2)

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flow - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Cash from operating activities:
Net income	$ 552	$ 442.7
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	103.8	96.3
Stock-based compensation expense	23.8	21.7
Deferred income tax provision (benefit)	1.9	0.1
Net change in components of working capital	(73.9)	(23.8)
Net change in other long-term assets and liabilities	(8.1)	(4.6)
Net cash provided by operating activities	599.5	532.4
Cash from investing activities:
Capital expenditures	(94.3)	(97.7)
Proceeds from disposals of property, plant and equipment	0.5	0.8
Purchases of investments	(11.9)	(56.7)
Sales and maturities of investments	87.6	10
Acquisitions, net of cash acquired	0	(113.2)
Other, net	1.1	0.2
Net cash used in investing activities	(17)	(256.6)
Cash from financing activities:
Proceeds from issuance of senior notes and other long-term debt	0	350.2
Repayments of senior notes and other long-term debt	(1.1)	(3.1)
(Repayments) borrowings under commercial paper programs, net	0	(387.5)
Payment of costs related to debt financing	(2.9)	(2.3)
Purchase of treasury stock	(153.8)	(166.9)
Proceeds from exercise of stock options	113.3	74.3
Distributions to and purchases of noncontrolling interests	0	(5.2)
Dividend payments	(131.7)	(124.9)
Net cash used in financing activities	(176.2)	(265.4)
Effect of exchange rate changes on cash and cash equivalents	(24.2)	7.6
Net increase (decrease) in cash and cash equivalents	382.1	18
Cash and cash equivalents balance, beginning of period	1,475	1,373.1	$ 1,373.1
Cash and cash equivalents balance, end of period	1,857.1	1,391.1	$ 1,475
Cash paid for:
Interest	32.8	34.9
Income taxes, net	$ 130.1	$ 116.1

Basis of Presentation and Princ

Basis of Presentation and Principles of Consolidation	3 Months Ended
	Mar. 31, 2024
Basis of Presentation and Principles of Consolidation
Basis of Presentation and Principles of Consolidation	Note 1—Basis of Presentation and Principles of Consolidation ​ The Condensed Consolidated Balance Sheets as of March 31, 2024 and December 31, 2023, and each of the related Condensed Consolidated Statements of Income, Condensed Consolidated Statements of Comprehensive Income and Condensed Consolidated Statements of Cash Flow for the three months ended March 31, 2024 and 2023, include the accounts of Amphenol Corporation and its subsidiaries (“Amphenol,” the “Company,” “we,” “our” or “us”). All material intercompany balances and transactions have been eliminated in consolidation. The condensed consolidated financial statements included herein are unaudited. In the opinion of management, the condensed consolidated financial statements reflect all adjustments, including normal recurring adjustments considered necessary for a fair presentation of the results, in conformity with accounting principles generally accepted in the United States of America. The results of operations for the three months ended March 31, 2024 are not necessarily indicative of the results to be expected for the full year. These condensed consolidated financial statements and the related notes should be read in conjunction with the consolidated financial statements and notes included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2023 (the “2023 Annual Report”).

New Accounting Pronouncements

New Accounting Pronouncements	3 Months Ended
	Mar. 31, 2024
New Accounting Pronouncements
New Accounting Pronouncements	Note 2—New Accounting Pronouncements ​ In November 2023, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures (“ASU 2023-07”), which amends ASC 280. The intent of ASU 2023-07 is to improve the disclosures around a public entity’s reportable segments and address requests from investors for additional, more detailed information about a reportable segment’s expenses by requiring entities to disclose on an annual and interim basis: (i) significant segment expenses that are regularly provided to the Chief Operating Decision Maker (“CODM”) and included within each reported measure of segment profit or loss and (ii) an amount for other segment items by reportable segment and a description of its composition, which represents the difference between segment revenue less segment expenses disclosed under the significant expense principle and each reported measure of segment profit or loss. Furthermore, entities will be required to: (i) provide all annual disclosures about a segment’s profit or loss and assets currently required under ASC 280 on an interim basis as well, (ii) clarify that an entity is not precluded from reporting additional measures of a segment’s profit or loss that are used by the CODM in assessing segment performance and deciding how to allocate resources, and (iii) disclose the title and position of the CODM and an explanation of how the CODM uses the reported measures of segment profit or loss in assessing segment performance and deciding how to allocate resources. ASU 2023-07 is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The Company is currently evaluating the potential impact of ASU 2023-07 on its consolidated financial statements and disclosures. ​ In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”). The intent of ASU 2023-09 is to improve the disclosures around a company’s rate reconciliation information and certain types of income taxes companies are required to pay. Specifically, these new disclosure requirements will provide more transparency regarding income taxes companies pay in the United States and other countries, along with more disclosure around a company’s rate reconciliation, among other new disclosure requirements, such that users of financial statements can get better information about how the operations, related tax risks, tax planning and operational opportunities of companies affect their effective tax rates and future cash flow prospects. ASU 2023-09 is effective for annual fiscal years beginning after December 15, 2024, with early adoption permitted for annual financial statements that have not yet been issued or made available for issuance. The amendments under ASU 2023-09 should be applied on a prospective basis, although retrospective application is permitted. The Company is currently evaluating the potential impact of ASU 2023-09 on its consolidated financial statements and disclosures. ​

Inventories

Inventories	3 Months Ended
	Mar. 31, 2024
Inventories
Inventories	Note 3—Inventories ​ Inventories consist of: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ 2024 2023 Raw materials and supplies $ 970.9 $ 964.7 ​ Work in process ​ 587.0 ​ 562.3 ​ Finished goods ​ 595.0 ​ 640.1 ​ ​ $ 2,152.9 $ 2,167.1 ​ ​

Debt

Debt	3 Months Ended
	Mar. 31, 2024
Debt
Debt	Note 4—Debt ​ The Company’s debt (net of any unamortized discount) consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2024 ​ December 31, 2023 ​ ​ ​ ​ Carrying ​ Approximate ​ Carrying ​ Approximate ​ ​ ​ Amount Fair Value Amount Fair Value Revolving Credit Facility ​ ​ ​ $ — $ — $ — $ — ​ U.S. Commercial Paper Program ​ ​ ​ — ​ — ​ — ​ — ​ Euro Commercial Paper Program ​ ​ ​ — ​ — ​ — ​ — ​ Term Loan Credit Facility ​ ​ ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ 3.20% Senior Notes due April 2024 ​ ​ ​ 350.0 ​ 349.9 ​ 350.0 ​ 348.4 ​ 2.050% Senior Notes due March 2025 ​ ​ ​ ​ 399.9 ​ ​ 387.7 ​ ​ 399.8 ​ ​ 386.8 ​ 4.750% Senior Notes due March 2026 ​ ​ ​ ​ 349.2 ​ ​ 347.5 ​ ​ 349.1 ​ ​ 350.6 ​ 0.750% Euro Senior Notes due May 2026 ​ ​ ​ ​ 539.3 ​ ​ 509.7 ​ ​ 551.7 ​ ​ 523.4 ​ 2.000% Euro Senior Notes due October 2028 ​ ​ ​ ​ 538.9 ​ ​ 515.1 ​ ​ 551.4 ​ ​ 531.4 ​ 4.350% Senior Notes due June 2029 ​ ​ ​ ​ 499.8 ​ ​ 486.9 ​ ​ 499.8 ​ ​ 497.2 ​ 2.800% Senior Notes due February 2030 ​ ​ ​ ​ 899.6 ​ ​ 804.2 ​ ​ 899.6 ​ ​ 817.6 ​ 2.200% Senior Notes due September 2031 ​ ​ ​ ​ 748.0 ​ ​ 620.6 ​ ​ 747.9 ​ ​ 629.9 ​ Other debt ​ ​ ​ 7.2 ​ 7.2 ​ 9.5 ​ 9.5 ​ Less: unamortized deferred debt issuance costs ​ ​ (22.5) ​ — ​ (21.5) ​ — ​ Total debt ​ ​ ​ 4,309.4 ​ 4,028.8 ​ 4,337.3 ​ 4,094.8 ​ Less: current portion ​ ​ ​ 752.5 ​ ​ 740.2 ​ 353.8 ​ 352.2 ​ Total long-term debt ​ ​ ​ $ 3,556.9 $ 3,288.6 $ 3,983.5 $ 3,742.6 ​ ​ Revolving Credit Facility ​ On March 21, 2024, the Company entered into a third amended and restated credit agreement, which amended and restated its $2,500.0 unsecured revolving credit facility, increasing the lenders’ aggregate unsecured revolving commitments under the facility by $500.0 to $3,000.0 (the “Revolving Credit Facility”). The Revolving Credit Facility matures in March 2029 and gives the Company and certain of its subsidiaries the ability to borrow, in various currencies, at a spread that varies, based on the Company’s debt rating, over certain currency-specific benchmark rates, which benchmark rates, in the case of U.S. dollar borrowings, are either the base rate or the adjusted term Secured Overnight Financing Rate (“SOFR”). The Revolving Credit Facility was undrawn on the date of the amendment. The Company may utilize the Revolving Credit Facility for general corporate purposes. outstanding borrowings under the revolving credit facility then in effect. The carrying value of any borrowings under the Revolving Credit Facility would approximate their fair value, primarily due to their market interest rates, and would be classified as Level 2 in the fair value hierarchy (Note 5). Any outstanding borrowings under the Revolving Credit Facility are classified as long-term debt in the accompanying Condensed Consolidated Balance Sheets. The Revolving Credit Facility requires payment of certain annual agency and commitment fees and requires that the Company satisfy certain financial covenants. ​ Term Loan Credit Facility ​ On April 19, 2022, the Company entered into a two-year . The Term Loan was undrawn at closing and was permitted to be drawn on up to occasions over the life of the facility. The Term Loan could be repaid at any time without premium or penalty, and, once repaid, could not be reborrowed. If drawn upon, the proceeds from the Term Loan were expected to be used for general corporate purposes. Interest rates under the Term Loan were based on a spread over either the base rate or the adjusted term SOFR, which spread varied based on the Company’s debt rating. The carrying value of any borrowings under the Term Loan would approximate their fair value, primarily due to its market interest rates, and would be classified as Level 2 in the fair value hierarchy (Note 5). outstanding borrowings under the Term Loan. The Term Loan required payment of certain commitment fees and required that the Company satisfy certain financial covenants. The Term Loan matured on April 19, 2024 without the Company drawing upon it throughout its term. ​ Commercial Paper Programs ​ The Company has a commercial paper program (the “U.S. Commercial Paper Program”) pursuant to which the Company may issue short-term unsecured commercial paper notes (the “USCP Notes” or “U.S. Commercial Paper”) in one or more private placements in the United States. The maturities of the USCP Notes vary but may not exceed from the date of issue. The USCP Notes are sold under customary terms in the commercial paper market and may be issued at par or a discount therefrom, and bear varying interest rates on a fixed or floating basis. On March 21, 2024, in conjunction with the increase in the capacity of the Revolving Credit Facility, the Company increased the borrowings available under its U.S. Commercial Paper Program by . As of March 31, 2024, the maximum aggregate principal amount outstanding of USCP Notes at any time is . The Company utilizes borrowings under the U.S. Commercial Paper Program for general corporate purposes, which, in recent years, have included fully or partially funding acquisitions, as well as repaying certain outstanding senior notes. The Company borrowed under the U.S. Commercial Paper Program throughout much of the first quarter of 2024, the proceeds of which were used for general corporate purposes. Before the end of the first quarter of 2024, the Company repaid all of its USCP Notes then outstanding. As of March 31, 2024 and December 31, 2023, there were USCP Notes outstanding. ​ The Company and one of its wholly owned European subsidiaries (the “Euro Issuer”) also have a commercial paper program (the “Euro Commercial Paper Program” and, together with the U.S. Commercial Paper Program, the “Commercial Paper Programs”), pursuant to which the Euro Issuer may issue short-term unsecured commercial paper notes (the “ECP Notes” and, together with the USCP Notes, the “Commercial Paper”), which are guaranteed by the Company and are to be issued outside of the United States. The maturities of the ECP Notes will vary but may not exceed 183 days from the date of issue. The ECP Notes are sold under customary terms in the commercial paper market and may be issued at par or a discount therefrom or a premium thereto and bear varying interest rates on a fixed or floating basis. The ECP Notes may be issued in Euros, Sterling, U.S. dollars or other currencies. The maximum aggregate principal amount outstanding of ECP Notes at any time is . The Company utilizes borrowings under the Euro Commercial Paper Program for general corporate purposes, which may include, for example, fully or partially funding acquisitions. The Company did not borrow under the Euro Commercial Paper Program during the first quarter of 2024, and, as of March 31, 2024 and December 31, 2023, there were ​ Amounts available under the Commercial Paper Programs may be borrowed, repaid and re-borrowed from time to time. In conjunction with the Revolving Credit Facility, as of March 31, 2024, the authorization from the Company’s Board of Directors (the “Board”) limits the maximum aggregate principal amount outstanding of USCP Notes, ECP Notes, and any other commercial paper or similar programs, along with outstanding amounts under the Revolving Credit Facility, at any time to in the aggregate. Revolving Credit Facility, as amounts undrawn under the Company’s Revolving Credit Facility are available to repay Commercial Paper, if necessary. Net proceeds of the issuances of Commercial Paper are expected to be used for general corporate purposes. Any outstanding Commercial Paper is classified as long-term debt in the accompanying Condensed Consolidated Balance Sheets since the Company has the intent and ability to refinance the Commercial Paper on a long-term basis using the Company’s Revolving Credit Facility. The carrying value of Commercial Paper approximates its fair value, primarily due to its market interest rates, and is classified as Level 2 in the fair value hierarchy (Note 5). ​ U.S. Senior Notes ​ On April 5, 2024, the Company issued three series of unsecured senior notes (collectively, the “New Senior Notes”): (i) of face value (the “2034 Senior Notes”). The New Senior Notes are unsecured and rank equally in right of payment with all of the Company’s other senior unsecured and unsubordinated indebtedness, including the Company’s guarantee of the Euro Issuer’s obligations under the Euro Notes. Interest on the New Senior Notes is payable semiannually on April 5 and October 5 of each year, commencing on October 5, 2024. Prior to March 5, 2027, the Company may redeem, from time to time, some or all of the 2027 Senior Notes at a redemption price equal to of the principal amount thereof, plus accrued and unpaid interest, if any, to the date of redemption, plus a make-whole premium. Prior to March 5, 2029, the Company may redeem, from time to time, some or all of the 2029 Senior Notes at a redemption price equal to of the principal amount thereof, plus accrued and unpaid interest, if any, to the date of redemption, plus a make-whole premium. Prior to January 5, 2034, the Company may redeem, from time to time, some or all of the 2034 Senior Notes at a redemption price equal to of the principal amount thereof, plus accrued and unpaid interest, if any, to the date of redemption, plus a make-whole premium. On or after such dates, the Company may redeem, from time to time, some or all of the respective series of the New Senior Notes at a redemption price equal to of the principal amount thereof, plus accrued and unpaid interest, if any, to the date of redemption. If the Company’s pending acquisition of the Carlisle Interconnect Technologies (“CIT”) business is not consummated on or prior to an agreed upon date or if the Company notifies the trustee that the acquisition will not be pursued at all, under certain circumstances, each series of the New Senior Notes will be subject to a special mandatory redemption, at a price equal to of the principal amount thereof, plus accrued and unpaid interest from the date of initial issuance, or the most recent date to which interest has been paid or provided for, whichever is later, to, but not including, the special mandatory redemption date. Absent a special mandatory redemption, the Company intends to use the net proceeds from the New Senior Notes, together with a combination of cash on hand and other debt financing (which could include borrowings under the Company’s Revolving Credit Facility and/or U.S. Commercial Paper Program), to fund the cash consideration for the Company’s pending CIT acquisition, as discussed in further detail in Note 11 herein, along with the fees and expenses related thereto. To the extent that the net proceeds from the New Senior Notes are not used for such purposes, such net proceeds shall be used for general corporate purposes. ​ On April 1, 2024, the Company used cash on hand to repay the $350.0 aggregate principal amount of unsecured 3.20% Senior Notes due April 1, 2024 upon maturity. ​ On March 30, 2023, the Company issued $350.0 aggregate principal amount of unsecured 4.750% Senior Notes due March 30, 2026 at 99.658% of face value (the “2026 Senior Notes”). The 2026 Senior Notes are unsecured and rank equally in right of payment with all of the Company’s other senior unsecured and unsubordinated indebtedness, including the Company’s guarantee of the Euro Issuer’s obligations under the Euro Notes. Interest on the 2026 Senior Notes is payable semiannually on March 30 and September 30 of each year, commencing on September 30, 2023. of the principal amount thereof, plus accrued and unpaid interest, if any, to, but not including, the date of redemption, plus a make-whole premium. The Company used the net proceeds from the 2026 Senior Notes to repay certain outstanding borrowings under the U.S. Commercial Paper Program. ​ All of the Company’s outstanding senior notes in the United States (the “U.S. Senior Notes”) are unsecured and rank equally in right of payment with all of the Company’s other senior unsecured and unsubordinated indebtedness, including the Company’s guarantee of the Euro Issuer’s obligations under the Euro Notes. Interest on each series of U.S. Senior Notes is payable semiannually. The Company may, at its option, redeem some or all of any series of U.S. ​ Euro Senior Notes ​ The Euro Issuer has two outstanding unsecured senior notes issued in Europe (collectively, the “Euro Notes” and the Euro Notes, together with the U.S. Senior Notes, the “Senior Notes”), each of which was issued with an aggregate principal amount of €500.0 . The Euro Senior Notes . The Euro Notes are unsecured and rank equally in right of payment with all of the Euro Issuer’s senior unsecured and unsubordinated indebtedness and are fully and unconditionally guaranteed on a senior unsecured basis by the Company. Interest on each series of Euro Notes is payable annually. The Company may, at its option, redeem some or all of either series of Euro Notes at any time, subject to certain terms and conditions, which include paying of the principal amount, plus accrued and unpaid interest, if any, to, but not including, the date of redemption, and, with certain exceptions, a make-whole premium. ​ The fair value of each series of Senior Notes is based on recent bid prices in an active market and is therefore classified as Level 1 in the fair value hierarchy (Note 5). The Senior Notes impose certain obligations on the Company and prohibit various actions by the Company unless it satisfies certain financial requirements.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2024
Fair Value Measurements
Fair Value Measurements	Note 5—Fair Value Measurements ​ Fair value is determined based on the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants. These requirements establish market or observable inputs as the preferred source of values. Assumptions based on hypothetical transactions are used in the absence of market inputs. The Company does not have any non-financial instruments accounted for at fair value on a recurring basis. ​ The valuation techniques required are based upon observable and unobservable inputs. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect the Company’s market assumptions. These two types of inputs create the following fair value hierarchy: ​ Level 1 Quoted prices for identical instruments in active markets. ​ Level 2 Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations whose inputs are observable or whose significant value drivers are observable. ​ Level 3 Significant inputs to the valuation model are unobservable. ​ The Company believes that the assets or liabilities currently subject to such standards with fair value disclosure requirements are primarily (i) debt instruments, (ii) pension plan assets, (iii) short- and long-term investments, (iv) derivative instruments and (v) assets acquired and liabilities and noncontrolling interests assumed as part of acquisition accounting. Each of these assets and liabilities is discussed below, with the exception of debt instruments, pension plan assets, and the fair value of assets acquired and liabilities and noncontrolling interests assumed as part of acquisition accounting, which are discussed in Note 4, Note 10 and Note 11, respectively, herein, in addition to the Notes to Consolidated Financial Statements in the 2023 Annual Report. Substantially all of the Company’s short- and long-term investments consist of certificates of deposit, which are considered as Level 2 in the fair value hierarchy. Long-term investments are recorded in Other long-term assets in the accompanying Condensed Consolidated Balance Sheets. The carrying amounts of these short- and long-term instruments, the vast majority of which are in non-U.S. bank accounts, approximate their respective fair values. The Company’s derivative instruments primarily consist of foreign exchange forward contracts, which are valued using bank quotations based on market observable inputs, such as forward and spot rates, and are therefore classified as Level 2 in the fair value hierarchy. The impact of the credit risk related to these derivative financial assets is immaterial. ​ The Company reviews the fair value hierarchy classifications on a quarterly basis and determines the appropriate classification of such assets and liabilities subject to the fair value hierarchy standards based on, among other things, the ability to observe valuation inputs. The fair values of the Company’s financial and non-financial assets and liabilities subject to such standards as of March 31, 2024 and December 31, 2023 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements ​ ​ ​ ​ ​ Quoted Prices in ​ Significant ​ Significant ​ ​ ​ ​ ​ Active Markets ​ Observable ​ Unobservable ​ ​ ​ ​ ​ for Identical ​ Inputs ​ Inputs ​ ​ Total ​ Assets (Level 1) ​ (Level 2) ​ (Level 3) March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Short-term investments ​ $ 106.4 ​ $ — ​ $ 106.4 ​ $ — Long-term investments ​ ​ 0.4 ​ ​ — ​ ​ 0.4 ​ ​ — Forward contracts ​ ​ (0.2) ​ ​ — ​ ​ (0.2) ​ ​ — Redeemable noncontrolling interests ​ ​ (30.9) ​ ​ — ​ ​ — ​ ​ (30.9) Total ​ $ 75.7 ​ $ — ​ $ 106.6 ​ $ (30.9) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Short-term investments ​ $ 185.2 ​ $ — ​ $ 185.2 ​ $ — Long-term investments ​ ​ 0.4 ​ ​ — ​ ​ 0.4 ​ ​ — Forward contracts ​ ​ (0.5) ​ ​ — ​ ​ (0.5) ​ ​ — Redeemable noncontrolling interests ​ ​ (30.7) ​ ​ — ​ ​ — ​ ​ (30.7) Total ​ $ 154.4 ​ $ — ​ $ 185.1 ​ $ (30.7) ​ The Company utilizes foreign exchange forward contracts, hedging instruments accounted for as cash flow hedges, in the management of foreign currency exposures. In addition, the Company also enters into foreign exchange forward contracts, accounted for as net investment hedges, to hedge our exposure to variability in the U.S. dollar equivalent of the net investments in certain foreign subsidiaries. As of March 31, 2024 and December 31, 2023, the Company had cash flow hedges . As of March 31, 2024 and December 31, 2023, the fair value of such foreign exchange forward contracts in the table above consisted of various outstanding foreign exchange forward contracts that are not designated as hedging instruments. During the three months ended March 31, 2024 and 2023, the amounts recognized in Accumulated other comprehensive income (loss) associated with foreign exchange forward contracts, as well as the amounts reclassified from Accumulated other comprehensive income (loss) to foreign exchange gain (loss), included in Cost of sales in the accompanying Condensed Consolidated Statements of Income, were not material. The fair values of the Company’s forward contracts are recorded within Prepaid expenses and other current assets, Other long-term assets, Other accrued expenses and Other long-term liabilities in the accompanying Condensed Consolidated Balance Sheets, depending on their value and remaining contractual period. ​ Certain acquisitions may result in noncontrolling interest holders who, in certain cases, are entitled to a put option, giving them the ability to put some or all of their redeemable interest in the shares of the acquiree to the Company. Specifically, if exercised by the noncontrolling interest holder, Amphenol would be required to purchase some or all of the option holder’s redeemable interest, at a redemption price during specified time period(s) stipulated in the respective acquisition agreement. The redeemable noncontrolling interests recorded on the accompanying Condensed Consolidated Balance Sheets relate to recent acquisitions, which, based on the terms of the respective acquisition agreements, will remain in temporary equity until the applicable put option is either fully exercised or expires. The redemption value of the redeemable noncontrolling interests is generally calculated using Level 3 unobservable inputs based on a multiple of earnings, which, for the redeemable noncontrolling interests currently outstanding, approximate fair value. As such, the redemption value is classified as Level 3 in the fair value hierarchy and is recorded as Redeemable noncontrolling interests on the Condensed Consolidated Balance Sheets as of March 31, 2024 and December 31, 2023. Refer to Note 7 herein for a rollforward of the Redeemable noncontrolling interests for the three months ended March 31, 2024 and 2023. ​ With the exception of the fair value of the assets acquired and liabilities assumed in connection with acquisition accounting, the Company does not have any other significant financial or non-financial assets and liabilities that are measured at fair value on a non-recurring basis.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2024
Income Taxes
Income Taxes	Note 6—Income Taxes ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, ​ ​ 2024 ​ 2023 ​ Provision for income taxes ​ $ (110.7) ​ $ (117.2) ​ Effective tax rate ​ 16.7 % 20.9 % ​ For the three months ended March 31, 2024 and 2023, stock option exercise activity had the impact of decreasing our Provision for income taxes by $29.7 and $17.1, respectively, and decreasing our effective tax rate by approximately 450 basis points and 310 basis points, respectively, due to the recognition of excess tax benefits within Provision for income taxes in the accompanying Condensed Consolidated Statements of Income. In addition, for the three months ended March 31, 2024, a discrete tax benefit of basis points. Acquisition-related expenses incurred during the three months ended March 31, 2023 had an immaterial effect on our effective tax rate. ​ The United States federal government enacted the Tax Cuts and Jobs Act (“Tax Act”) in December 2017. As a result, in 2017, the Company recorded a transition tax (“Transition Tax”) related to the deemed repatriation of the accumulated unremitted earnings and profits of the Company’s foreign subsidiaries. The Company expects to pay its seventh annual installment of the Transition Tax, net of applicable tax credits and deductions, in the second quarter of 2024, and will pay the balance of the Transition Tax, net of applicable tax credits and deductions, in 2025, as permitted under the Tax Act. The current and long-term portions of the Transition Tax are recorded in Accrued income taxes and Other long-term liabilities, respectively, on the Condensed Consolidated Balance Sheets as of March 31, 2024 and December 31, 2023. ​ The Company operates in the U.S. and numerous foreign taxable jurisdictions, and at any point in time has numerous audits underway at various stages of completion. With few exceptions, the Company is subject to income tax examinations by tax authorities for the years 2017 and after. The Company is generally not able to precisely estimate the ultimate settlement amounts or timing until the close of an audit. The Company evaluates its tax positions and establishes liabilities for uncertain tax positions that may be challenged by tax authorities and may not be fully sustained, despite the Company’s belief that the underlying tax positions are fully supportable. As of March 31, 2024, the amount of unrecognized tax benefits, including penalties and interest, which if recognized would impact the effective tax rate, was approximately . Unrecognized tax benefits are reviewed on an ongoing basis and are adjusted for changing facts and circumstances, including the progress of tax audits and the closing of statutes of limitations. Based on information currently available, management anticipates that over the next 12-month period, audit activity could be completed and statutes of limitations may close relating to existing unrecognized tax benefits of approximately ​ Inflation Reduction Act of 2022 ​ On August 16, 2022, the President of the United States signed into law the Inflation Reduction Act of 2022 (the “IRA”), a tax and spending package that introduces several tax-related provisions, including a 15% corporate alternative minimum tax (“CAMT”) on certain large corporations and a 1% excise tax on certain corporate stock repurchases. Companies are required to reassess their valuation allowances for certain affected deferred tax assets in the period of enactment but do not need to remeasure deferred tax balances for the related tax accounting implications of the CAMT. The IRA provisions, which became effective for Amphenol beginning on January 1, 2023, did not have a material impact on the Company during the three months ended March 31, 2024 and 2023. While the full impact of these provisions in the future depends on several factors, including interpretive regulatory guidance, which has not yet been released, the Company does not currently believe that the provisions of the IRA, including several other non-tax related provisions, will have a material impact on its financial condition, results of operations, liquidity and cash flows.

Stockholders' Equity and Noncon

Stockholders' Equity and Noncontrolling Interests	3 Months Ended
	Mar. 31, 2024
Stockholders' Equity and Noncontrolling Interests
Stockholders' Equity and Noncontrolling Interests	Note 7—Stockholders’ Equity and Noncontrolling Interests ​ Net income attributable to noncontrolling interests is classified below net income. Earnings per share is determined after the impact of the noncontrolling interests’ share in net income of the Company. In addition, the equity attributable to noncontrolling interests is presented as a separate caption within equity. ​ A rollforward of consolidated changes in equity and redeemable noncontrolling interests for the three months ended March 31, 2024 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Stockholders’ equity attributable to Amphenol Corporation ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ ​ ​ ​ ​ ​ Redeemable ​ Common Stock ​ Treasury Stock ​ Additional ​ ​ ​ ​ Other ​ Non- ​ ​ ​ ​ Non- ​ Shares ​ ​ ​ ​ Shares ​ ​ ​ ​ Paid-In ​ Retained ​ Comprehensive ​ controlling ​ Total ​ controlling ​ (in millions) Amount (in millions) Amount Capital Earnings Loss Interests (1) Equity Interests ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance as of December 31, 2023 600.6 $ 0.6 (1.7) $ (142.8) $ 3,101.2 $ 5,921.1 $ (533.6) $ 49.3 $ 8,395.8 $ 30.7 Net income ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 548.7 ​ ​ ​ ​ 2.9 ​ 551.6 ​ ​ 0.4 Other comprehensive income (loss) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (69.3) ​ (0.8) ​ (70.1) ​ ​ (0.2) Capital contributions from noncontrolling interests ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 0.8 ​ 0.8 ​ ​ ​ Purchase of treasury stock ​ ​ ​ ​ ​ (1.4) ​ (153.8) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (153.8) ​ ​ ​ Retirement of treasury stock (1.4) ​ ​ — ​ 1.4 ​ 153.8 ​ ​ ​ ​ (153.8) ​ ​ ​ ​ ​ ​ ​ — ​ ​ ​ Stock options exercised 2.8 ​ ​ — ​ 0.4 ​ ​ 39.0 ​ 99.1 ​ ​ (20.4) ​ ​ ​ ​ ​ ​ ​ 117.7 ​ ​ ​ Dividends declared ($0.22 per common share) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (132.1) ​ ​ ​ ​ ​ ​ ​ (132.1) ​ ​ ​ Stock-based compensation expense ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 23.8 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 23.8 ​ ​ ​ Balance as of March 31, 2024 602.0 ​ $ 0.6 ​ (1.3) ​ $ (103.8) ​ $ 3,224.1 ​ $ 6,163.5 ​ $ (602.9) ​ $ 52.2 ​ $ 8,733.7 ​ $ 30.9 (1) Excludes redeemable noncontrolling interests. ​ A rollforward of consolidated changes in equity and redeemable noncontrolling interests for the three months ended March 31, 2023 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Stockholders’ equity attributable to Amphenol Corporation ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ ​ ​ ​ ​ ​ Redeemable ​ Common Stock ​ Treasury Stock ​ Additional ​ ​ ​ ​ Other ​ Non- ​ ​ ​ ​ Non- ​ Shares ​ ​ ​ ​ Shares ​ ​ ​ ​ Paid-In ​ Retained ​ Comprehensive ​ controlling ​ Total ​ controlling ​ (in millions) Amount (in millions) Amount Capital Earnings Loss Interests (1) Equity Interests ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance as of December 31, 2022 596.0 $ 0.6 (1.2) $ (79.8) $ 2,650.4 $ 4,979.4 $ (535.0) $ 57.9 $ 7,073.5 $ 20.6 Net income ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 439.2 ​ ​ ​ ​ 3.2 ​ 442.4 ​ 0.3 Other comprehensive income (loss) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 42.4 ​ 0.8 ​ 43.2 ​ — Acquisitions resulting in noncontrolling interests ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 0.8 ​ 0.8 ​ ​ Distributions to shareholders of noncontrolling interests ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (5.2) ​ (5.2) ​ ​ Purchase of treasury stock ​ ​ ​ ​ ​ (2.1) ​ (166.9) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (166.9) ​ ​ Retirement of treasury stock (2.1) ​ ​ — ​ 2.1 ​ 166.9 ​ ​ ​ ​ (166.9) ​ ​ ​ ​ ​ ​ ​ — ​ ​ Stock options exercised 2.4 ​ ​ — ​ 0.2 ​ ​ 10.1 ​ 76.4 ​ ​ (5.4) ​ ​ ​ ​ ​ ​ ​ 81.1 ​ ​ Dividends declared ($0.21 per common share) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (125.0) ​ ​ ​ ​ ​ ​ ​ (125.0) ​ ​ Stock-based compensation expense ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 21.7 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 21.7 ​ ​ Balance as of March 31, 2023 596.3 ​ $ 0.6 ​ (1.0) ​ $ (69.7) ​ $ 2,748.5 ​ $ 5,121.3 ​ $ (492.6) ​ $ 57.5 ​ $ 7,365.6 ​ $ 20.9 (1) Excludes redeemable noncontrolling interests. ​ ​ Stock Repurchase Programs ​ On April 27, 2021, the Board authorized a stock repurchase program under which the Company may purchase up to $2,000.0 of the Company’s Class A Common Stock (“Common Stock”) during the three-year period ending April 27, 2024 (the “2021 Stock Repurchase Program”). During the three months ended March 31, 2024, the Company repurchased under the 2021 Stock Repurchase Program. All repurchased shares during the first three months of 2024 were retired by the Company. under the 2021 Stock Repurchase Program. All repurchased shares during the first three months of 2023 were retired by the Company. From April 1, 2024 to April 26, 2024, the Company repurchased ​ On April 23, 2024, the Board authorized a new stock repurchase program under which the Company may purchase up to $2,000.0 of the Company’s Common Stock during the three-year period ending on the close of business on April 28, 2027 (the “2024 Stock Repurchase Program”). The 2024 Stock Repurchase Program becomes effective on April 29, 2024. The ​ Dividends ​ Contingent upon declaration by the Board, the Company pays a quarterly dividend on shares of its Common Stock. The following table summarizes the dividends declared and paid during the three months ended March 31, 2024 and 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2024 ​ 2023 ​ Dividends declared ​ $ 132.1 ​ $ 125.0 ​ Dividends paid (including those declared in the prior year) ​ 131.7 ​ 124.9 ​ ​ On October 24, 2023, the Board approved an increase to the Company’s quarterly dividend rate from $0.21 per share to $0.22 per share, effective with dividends declared in the fourth quarter of 2023, contingent upon declaration by the Board.

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2024
Stock-Based Compensation
Stock-Based Compensation	Note 8—Stock-Based Compensation ​ For the three months ended March 31, 2024 and 2023, the Company’s Income before income taxes was reduced for stock-based compensation expense of $23.8 and $21.7 , respectively. In addition, for the three months ended March 31, 2024 and 2023, the Company recognized aggregate income tax benefits (associated with stock-based compensation) of , respectively, in Provision for income taxes in the accompanying Condensed Consolidated Statements of Income. These aggregate income tax benefits during the three months ended March 31, 2024 and 2023 include excess tax benefits of ​ The impact associated with recognizing excess tax benefits from option exercises in the provision for income taxes on our consolidated financial statements could result in significant fluctuations in our effective tax rate in the future, since the provision for income taxes will be impacted by the timing and intrinsic value of future stock-based compensation award exercises. ​ Stock-based compensation expense includes the estimated effects of forfeitures, which are adjusted over the requisite service period to the extent actual forfeitures differ or are expected to differ from such estimates. Changes in estimated forfeitures are recognized in the period of change and impact the amount of expense to be recognized in future periods. The expense incurred for stock-based compensation plans is included in Selling, general and administrative expenses in the accompanying Condensed Consolidated Statements of Income. ​ Stock Options ​ In May 2017, the Company adopted the 2017 Stock Purchase and Option Plan for Key Employees of Amphenol and Subsidiaries (the “2017 Employee Option Plan”), which provided for the issuance of 60,000,000 shares. In March 2021, the Board authorized and approved the Amended and Restated 2017 Stock Purchase and Option Plan for Key Employees of Amphenol and Subsidiaries (the “Amended 2017 Employee Option Plan” and, together with the 2017 Employee Option Plan, the “2017 Option Plan”), which among other things, increased the number of shares reserved for issuance under the plan by 40,000,000 shares. The Amended 2017 Employee Option Plan was approved by the Company’s stockholders and became effective on May 19, 2021. As of March 31, 2024, there were shares of Common Stock available for the granting of additional stock options under the 2017 Option Plan. Prior to the approval of the 2017 Employee Option Plan, the Company issued stock options under the 2009 Stock Purchase and Option Plan for Key Employees of Amphenol and Subsidiaries, and its amendment (the “2009 Employee Option Plan”). 2017 2009 from the date of grant. ​ Stock option activity for the three months ended March 31, 2024 was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ Average ​ Aggregate ​ ​ ​ Weighted ​ Remaining ​ Intrinsic ​ ​ ​ Average ​ Contractual ​ Value ​ ​ Options Exercise Price Term (in years) (in millions) Options outstanding at January 1, 2024 60,390,162 ​ $ 50.45 5.81 ​ $ 2,939.5 ​ Options granted 58,031 ​ 90.72 ​ ​ ​ ​ ​ ​ Options exercised (3,156,425) ​ 37.27 ​ ​ ​ ​ ​ ​ Options forfeited (43,137) ​ 65.02 ​ ​ ​ ​ ​ ​ Options outstanding at March 31, 2024 57,248,631 ​ $ 51.21 5.69 ​ $ 3,671.9 ​ Vested and non-vested options expected to vest at March 31, 2024 55,794,585 ​ $ 50.80 5.63 ​ $ 3,601.3 ​ Exercisable options at March 31, 2024 34,849,870 ​ $ 43.54 4.53 ​ $ 2,502.7 ​ ​ A summary of the status of the Company’s non-vested options as of March 31, 2024 and changes during the three months then ended is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ Average ​ ​ ​ ​ ​ Fair Value at ​ ​ ​ Options ​ Grant Date Non-vested options at January 1, 2024 22,523,981 ​ $ 14.57 ​ Options granted 58,031 ​ 26.36 ​ Options vested (146,726) ​ 15.79 ​ Options forfeited (36,525) ​ 17.73 ​ Non-vested options at March 31, 2024 22,398,761 ​ $ 14.58 ​ ​ During the three months ended March 31, 2024 and 2023, the following activity occurred under the Company’s option plans: ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ March 31, ​ 2024 ​ 2023 Total intrinsic value of stock options exercised $ 215.8 ​ $ 125.7 Total fair value of stock options vested 2.3 ​ 2.3 ​ As of March 31, 2024, the total compensation cost related to non-vested options not yet recognized was approximately $228.1 with a weighted average expected amortization period of 3.19 years. ​ The grant-date fair value of each option grant under the 2009 Employee Option Plan and the 2017 Option Plan is estimated using the Black-Scholes option pricing model. The grant-date fair value of each share grant is determined based on the closing share price of the Company’s Common Stock on the date of the grant. The fair value is then amortized on a straight-line basis over the requisite service period of the awards, which is generally the vesting period. Use of a valuation model for option grants requires management to make certain assumptions with respect to selected model inputs. Expected share price volatility is calculated based on the historical volatility of the Common Stock and implied volatility derived from related exchange traded options. The average expected life is based on the contractual term of the option and expected exercise and historical experience. The risk-free interest rate is based on U.S. Treasury zero-coupon issuances with a remaining term equal to the expected life assumed at the date of grant. The expected annual dividend per share is based on the Company’s dividend rate. ​ Phantom Stock ​ On June 5, 2023, the Company granted 2,375 shares of phantom stock to each then-current non-employee director (19,000 shares in the aggregate), which will vest and, pursuant to written elections made by each non-employee director, convert into unrestricted shares of the Company’s Common Stock on the earlier of May 19, 2024 or the day immediately prior to the date of the 2024 annual meeting of the Company’s stockholders. As of March 31, 2024, the total compensation cost related to non-vested shares of phantom stock not yet recognized was approximately

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2024
Earnings Per Share
Earnings Per Share	Note 9—Earnings Per Share ​ Basic earnings per common share (“EPS”) is computed by dividing net income attributable to Amphenol Corporation by the weighted average number of common shares outstanding. Diluted EPS is computed by dividing net income attributable to Amphenol Corporation by the weighted average number of outstanding common shares, including dilutive common shares, the dilutive effect of which relates to stock options. The following is a reconciliation of the basic weighted average common shares outs ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, (dollars and shares in millions, except per share data) 2024 2023 Net income attributable to Amphenol Corporation stockholders ​ $ 548.7 ​ $ 439.2 ​ ​ ​ ​ ​ ​ ​ Weighted average common shares outstanding — Basic ​ 600.0 ​ 595.1 Effect of dilutive stock options ​ 27.9 ​ 24.8 Weighted average common shares outstanding — Diluted ​ 627.9 ​ 619.9 ​ ​ ​ ​ ​ ​ ​ Net income attributable to Amphenol Corporation per common share — Basic ​ $ 0.91 ​ $ 0.74 ​ ​ ​ ​ ​ ​ ​ Net income attributable to Amphenol Corporation per common share — Diluted ​ $ 0.87 ​ $ 0.71 ​ Excluded from the computations above were anti-dilutive common shares (primarily related to outstanding stock options) of 0.1 million and 7.1 million for the three months ended March 31, 2024 and 2023, respectively.

Benefit Plans and Other Postret

Benefit Plans and Other Postretirement Benefits	3 Months Ended
	Mar. 31, 2024
Benefit Plans and Other Postretirement Benefits
Benefit Plans and Other Postretirement Benefits	Note 10—Benefit Plans and Other Postretirement Benefits ​ The Company and certain of its domestic subsidiaries have defined benefit pension plans (the “U.S. Plans”), which cover certain U.S. employees and which represent the majority of the plan assets and benefit obligations of the aggregate defined benefit plans of the Company. The U.S. Plans’ benefits are generally based on years of service and compensation and are generally noncontributory. The Company has an unfunded Supplemental Employee Retirement Plan (“SERP”), a defined benefit pension plan, which provides for the payment of the portion of annual pension that cannot be paid from the retirement plan as a result of regulatory limitations on average compensation for purposes of the benefit computation. The majority of U.S. employees are not covered by the U.S. Plans and are instead covered by various defined contribution plans. Certain foreign subsidiaries have defined benefit plans covering their employees (the “Foreign Plans” and, together with the U.S. Plans and SERP, the “Plans”). ​ The following is a summary, based on the most recent actuarial valuations of the Company’s net cost for pension benefits, of the Plans for the three months ended March 31, 2024 and 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2024 2023 Service cost $ 1.0 ​ $ 1.9 Interest cost ​ 6.1 ​ 6.5 Expected return on plan assets ​ (7.2) ​ (7.3) Amortization of prior service cost ​ 0.3 ​ 0.4 Amortization of net actuarial losses ​ 1.0 ​ 0.6 Net pension expense $ 1.2 ​ $ 2.1 ​ There is no current requirement for cash contributions to any of the U.S. Plans, and the Company plans to evaluate annually, based on actuarial calculations and the investment performance of the Plans’ assets, the timing and amount of cash contributions in the future, if any. ​ The Company offers various defined contribution plans for certain U.S. and foreign employees. Participation in these plans is based on certain eligibility requirements. The Company matches employee contributions to the U.S. defined contribution plans up to a maximum of of eligible compensation. During the three months ended March 31, 2024 and 2023, the Company provided matching contributions to the U.S. defined contribution plans of approximately

Acquisitions

Acquisitions	3 Months Ended
	Mar. 31, 2024
Acquisitions
Acquisitions	Note 11—Acquisitions ​ On January 30, 2024 , the Company entered into a definitive stock purchase agreement by and between the Company and Carlisle Companies Incorporated (“Carlisle”), agreeing to acquire the CIT business of Carlisle for an aggregate purchase price of $2,025 in cash, subject to customary post-closing adjustments. The acquisition is expected to be completed by the end of the second quarter of 2024 and is subject to certain regulatory approvals and other customary closing conditions. The Company expects to finance the CIT acquisition through a combination of the net proceeds from the New Senior Notes, as discussed in Note 4 herein, together with a combination of cash on hand and other debt financing, which could include borrowings under the Company’s Revolving Credit Facility and/or U.S. Commercial Paper Program. CIT, headquartered in St. Augustine, FL, is a leading global supplier of harsh environment interconnect solutions, primarily to the commercial aerospace, defense and industrial end markets. CIT’s wide range of products include wire and cable, cable assemblies, contacts, connectors and sensors, which, management believes, are highly complementary to Amphenol’s existing interconnect and sensor solutions. If and when the acquisition is consummated, the Company expects to report the CIT business within its Harsh Environment Solutions segment. ​ 2023 Acquisitions ​ During the year ended December 31, 2023, the Company completed 10 acquisitions (the “2023 Acquisitions”) for approximately $970.4 , net of cash acquired. acquisitions have been included in the Communications Solutions segment. The 2023 Acquisitions were each funded using cash on hand or borrowings under our Commercial Paper Programs, or a combination thereof. of the 2023 Acquisitions, which closed in the second quarter of 2023, represented a bargain purchase, where the estimated fair value of assets acquired, net of liabilities assumed, exceeded the purchase price. The Company recognized a non-cash gain of ​ As of March 31, 2024, the 2023 Acquisitions resulted in the recognition of $ 658.8 of goodwill and $ 153.2 of definite-lived intangible assets, comprised of customer relationships, proprietary technology and acquired backlog, with the remainder of the purchase price being allocated to other identifiable assets acquired and liabilities and noncontrolling interests assumed. These definite-lived intangible assets are being amortized based upon the underlying pattern of economic benefit as reflected by the future net cash inflows, with the acquired customer relationships and proprietary technology having useful lives ranging from 6 to 12 years and the acquired backlog having a useful life of approximately 0.25 years. The excess purchase price over the fair value of the underlying net assets acquired was allocated to goodwill, which primarily represents the value of the assembled workforce along with other intangible assets acquired that do not qualify for separate recognition. The Company expects that approximately $ 165 of the goodwill recognized from the 2023 Acquisitions will be deductible for tax purposes. ​ The Company completed the acquisition accounting, including the analyses of the fair value of assets acquired and liabilities assumed, for one of the 2023 Acquisitions, and its final assessment of values did not differ materially from its previous preliminary assessment. The Company is in the process of analyzing and completing the allocation of the fair value of assets acquired and liabilities assumed for each of the other 2023 Acquisitions. Since the current purchase price allocations for such other acquisitions are based on preliminary assessments made by management as of March 31, 2024, the acquisition accounting is subject to final adjustments, and it is possible that the final assessments of values may differ from our preliminary assessments. The operating results of the 2023 Acquisitions were included in the Condensed Consolidated Statements of Income since their respective dates of acquisition. Pro forma financial information, as well as further details regarding the purchase price allocations related to these acquisitions, were not presented, since the 2023 Acquisitions were not material, either individually or in the aggregate, to the Company’s financial results. ​ During the three months ended March 31, 2023, the Company incurred $5.4 ($4.0 after-tax) of acquisition-related expenses, comprised of the amortization related to the value associated with acquired backlog resulting from an acquisition that closed in the first quarter of 2023. Such acquisition-related expenses are presented separately in the Condensed Consolidated Statements of Income.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	3 Months Ended
	Mar. 31, 2024
Goodwill and Other Intangible Assets
Goodwill and Other Intangible Assets	Note 12—Goodwill and Other Intangible Assets ​ The changes in the carrying amount of goodwill by segment were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Harsh ​ ​ Interconnect ​ ​ ​ ​ Environment ​ Communications ​ and Sensor ​ ​ ​ ​ ​ Solutions ​ Solutions ​ Systems ​ Total Goodwill at December 31, 2023 ​ $ 2,009.3 ​ $ 2,977.5 ​ $ 2,105.6 ​ $ 7,092.4 ​ Acquisition-related ​ 1.2 ​ 4.5 ​ 43.7 ​ 49.4 ​ Foreign currency translation ​ (9.2) ​ (9.5) ​ (22.6) ​ (41.3) ​ Goodwill at March 31, 2024 ​ $ 2,001.3 ​ $ 2,972.5 ​ $ 2,126.7 ​ $ 7,100.5 ​ ​ Other than goodwill noted above, the Company’s intangible assets as of March 31, 2024 and December 31, 2023 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2024 ​ December 31, 2023 ​ Weighted ​ Gross ​ Net Gross ​ Net ​ Average ​ Carrying ​ Accumulated ​ Carrying ​ Carrying ​ Accumulated ​ Carrying ​ Life (years) ​ Amount ​ Amortization ​ Amount ​ Amount ​ Amortization ​ Amount Customer relationships 10 ​ $ 780.2 ​ $ 462.5 ​ $ 317.7 ​ $ 782.6 ​ $ 450.6 ​ $ 332.0 Proprietary technology 13 ​ 350.8 ​ 152.2 ​ ​ 198.6 ​ 365.1 ​ 146.1 ​ ​ 219.0 Backlog and other 1 ​ 99.4 ​ 99.4 ​ ​ — ​ 114.1 ​ 99.4 ​ ​ 14.7 Total intangible assets (definite-lived) 10 ​ ​ 1,230.4 ​ ​ 714.1 ​ ​ 516.3 ​ ​ 1,261.8 ​ ​ 696.1 ​ ​ 565.7 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Trade names (indefinite-lived) ​ ​ ​ 269.1 ​ ​ ​ ​ ​ 269.1 ​ ​ 269.1 ​ ​ ​ ​ ​ 269.1 ​ ​ ​ $ 1,499.5 ​ $ 714.1 ​ $ 785.4 ​ $ 1,530.9 ​ $ 696.1 ​ $ 834.8 ​ The decrease in the gross carrying amount of intangible assets in the first three months of 2024 was primarily driven by measurement period adjustments related to certain intangible assets associated with acquisitions that closed late in 2023. Amortization expense for the three months ended March 31, 2024 and 2023 was approximately , respectively. Amortization expense for the three months ended March 31, 2023 included related to the amortization of acquired backlog resulting from an acquisition that closed in the first quarter of 2023. As of March 31, 2024, amortization expense relating to the Company’s current intangible assets estimated for the remainder of 2024 is approximately

Reportable Business Segments

Reportable Business Segments	3 Months Ended
	Mar. 31, 2024
Reportable Business Segments
Reportable Business Segments	Note 13—Reportable Business Segments ​ The Company organizes its reportable business segments based on the manner in which management evaluates the performance of the Company, combined with the nature of the individual business activities and the product-based solutions offered. The Company aligns its businesses into the following ​ ● Harsh Environment Solutions – the Harsh Environment Solutions segment designs, manufactures and markets a broad range of ruggedized interconnect products, including connectors and interconnect systems, printed circuits and printed circuit assemblies and other products for use in the industrial, defense, commercial aerospace, automotive, mobile networks and information technology and data communications end markets. ​ ● Communications Solutions – the Communications Solutions segment designs, manufactures and markets a broad range of connector and interconnect systems, including high speed, radio frequency, power, fiber optic and other products, together with antennas, for use in the information technology and data communications, mobile devices, industrial, mobile networks, broadband communications, automotive, commercial aerospace and defense end markets. ​ ● Interconnect and Sensor Systems – the Interconnect and Sensor Systems segment designs, manufactures and markets a broad range of sensors, sensor-based systems, connectors and value-add interconnect systems used in the automotive, industrial, information technology and data communications, mobile networks, defense and commercial aerospace end markets. ​ This segment structure reflects (i) the manner in which the Chief Operating Decision Maker (“CODM”), who is the Company’s Chief Executive Officer, regularly assesses information for decision-making purposes, including the allocation of resources, and (ii) how the Company operates its businesses, assesses performance, and communicates results and strategy, among other items, to the Board and its stockholders. The Company has segment managers to lead their respective reportable business segments, each reporting directly to the Chief Executive Officer. The accounting policies of the segments are the same as those for the Company as a whole and are described herein and in Note 1 of the Notes to Consolidated Financial Statements in the 2023 Annual Report. The Company evaluates the performance of the segments and allocates resources to each of them based on, among other things, profit or loss from operations before certain corporate and other related items such as interest, stock-based compensation expense, income taxes, amortization related to certain intangible assets and nonrecurring gains and losses. Assets are reviewed by the CODM on a consolidated basis and therefore are not presented by reportable business segment. ​ Net sales by segment for the three months ended March 31, 2024 and 2023 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ External ​ Intersegment Three Months Ended March 31, ​ 2024 ​ 2023 ​ 2024 ​ 2023 Harsh Environment Solutions $ 916.0 ​ $ 854.2 ​ $ 19.6 ​ $ 23.8 Communications Solutions ​ ​ 1,265.7 ​ ​ 1,126.7 ​ ​ 11.2 ​ ​ 13.9 Interconnect and Sensor Systems ​ ​ 1,074.6 ​ ​ 993.1 ​ ​ 5.1 ​ ​ 5.1 Consolidated Net sales ​ $ 3,256.3 ​ $ 2,974.0 ​ $ 35.9 ​ $ 42.8 ​ Segment operating income and the reconciliation of segment operating income to consolidated income before income taxes for the three months ended March 31, 2024 and 2023 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2024 ​ 2023 Segment operating income: ​ ​ ​ ​ ​ ​ Harsh Environment Solutions ​ $ 244.4 ​ $ 226.3 Communications Solutions ​ ​ 286.2 ​ ​ 230.6 Interconnect and Sensor Systems ​ ​ 195.4 ​ ​ 178.8 Total segment operating income ​ ​ 726.0 ​ ​ 635.7 ​ ​ ​ ​ ​ ​ ​ Corporate / Other: ​ ​ ​ ​ ​ ​ Stock-based compensation expense ​ ​ (23.8) ​ ​ (21.7) Acquisition-related expenses ​ ​ — ​ ​ (5.4) Other operating expenses ​ ​ (17.4) ​ ​ (16.9) Interest expense ​ ​ (38.1) ​ ​ (35.9) Other income (expense), net ​ ​ 16.0 ​ ​ 4.1 ​ ​ ​ ​ ​ ​ ​ Income before income taxes ​ $ 662.7 ​ $ 559.9 ​ Depreciation and amortization expense by segment for the three months ended March 31, 2024 and 2023 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2024 ​ 2023 Harsh Environment Solutions $ 22.7 ​ $ 24.5 Communications Solutions ​ ​ 45.1 ​ ​ 39.2 Interconnect and Sensor Systems ​ ​ 33.9 ​ ​ 31.0 Corporate / Other ​ ​ 2.1 ​ ​ 1.6 Total ​ $ 103.8 ​ $ 96.3 ​

Revenue Recognition

Revenue Recognition	3 Months Ended
	Mar. 31, 2024
Revenue Recognition
Revenue Recognition	Note 14—Revenue Recognition ​ Revenues consist of product sales to either end customers and their appointed contract manufacturers (including original equipment manufacturers) or to distributors, and the vast majority of our sales are recognized at a point-in-time under the core principle of recognizing revenue when control transfers to the customer. With limited exceptions, the Company recognizes revenue at the point in time when we ship or deliver the product from our manufacturing facility to our customer, when our customer accepts and has legal title of the goods, and where the Company has a present right to payment for such goods. For the three months ended March 31, 2024 and 2023, less than of our net sales were recognized over time, where the associated contracts relate to the sale of goods with no alternative use as they are only sold to a single customer and whose underlying contract terms provide the Company with an enforceable right to payment, including a reasonable profit margin, for performance completed to date, in the event of customer termination. Since we typically invoice our customers at the same time that we satisfy our performance obligations, contract assets and contract liabilities related to our contracts with customers recorded in the Condensed Consolidated Balance Sheets were not material as of March 31, 2024 and December 31, 2023. These amounts are recorded in the accompanying Condensed Consolidated Balance Sheets within Prepaid expenses and other current assets or Other accrued expenses as of March 31, 2024 and December 31, 2023. ​ The Company receives customer orders negotiated with multiple delivery dates that may extend across more than one reporting period until the contract is fulfilled, the end of the order period is reached, or a pre-determined maximum order value has been reached. Orders typically fluctuate from quarter to quarter based on customer demand and general business conditions. It is generally expected that a substantial portion of our remaining performance obligations will be fulfilled within . Since our performance obligations are part of contracts that generally have original durations of disclosed the aggregate amount of transaction prices associated with unsatisfied or partially unsatisfied performance obligations as of March 31, 2024. ​ While the Company typically offers standard product warranty coverage that provides assurance that our products will conform to the contractually agreed-upon specifications for a limited period from the date of shipment, the Company’s warranty liabilities as of March 31, 2024 and December 31, 2023, and related warranty expense for the three months ended March 31, 2024 and 2023, have not been and were not material in the accompanying Condensed Consolidated Financial Statements. ​ Disaggregation of Net Sales ​ The following table shows our net sales disaggregated into categories the Company considers meaningful to depict how the nature, amount, timing and uncertainty of revenue and cash flows are affected by economic factors for the three months ended March 31, 2024 and 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Harsh ​ ​ ​ ​ ​ ​ ​ ​ Environment ​ Communications ​ Interconnect and ​ Total Reportable ​ ​ Solutions ​ Solutions ​ Sensor Systems ​ Business Segments Three Months Ended March 31, 2024 2023 2024 2023 2024 2023 ​ 2024 2023 Net sales by: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Sales channel: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ End customers and contract manufacturers ​ $ 675.3 $ 623.8 $ 990.9 $ 890.8 $ 1,032.0 $ 950.5 ​ $ 2,698.2 $ 2,465.1 Distributors and resellers ​ 240.7 ​ 230.4 ​ 274.8 ​ 235.9 ​ 42.6 ​ 42.6 ​ 558.1 ​ 508.9 ​ ​ $ 916.0 ​ $ 854.2 ​ $ 1,265.7 ​ $ 1,126.7 ​ $ 1,074.6 ​ $ 993.1 ​ $ 3,256.3 ​ $ 2,974.0 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ United States ​ $ 455.1 ​ $ 418.8 ​ $ 346.6 ​ $ 336.2 ​ $ 311.4 ​ $ 297.3 ​ $ 1,113.1 ​ $ 1,052.3 China ​ 81.0 ​ 86.3 ​ 374.2 ​ 350.0 ​ 215.2 ​ 182.8 ​ ​ 670.4 ​ ​ 619.1 Other foreign locations ​ 379.9 ​ 349.1 ​ 544.9 ​ 440.5 ​ 548.0 ​ 513.0 ​ 1,472.8 ​ ​ 1,302.6 ​ ​ $ 916.0 ​ $ 854.2 ​ $ 1,265.7 ​ $ 1,126.7 ​ $ 1,074.6 ​ $ 993.1 ​ $ 3,256.3 ​ $ 2,974.0 ​ Net sales by geographic area are based on the customer location to which the product is shipped. It is impracticable to disclose net sales by product or group of products.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2024
Commitments and Contingencies
Commitments and Contingencies	Note 15—Commitments and Contingencies ​ The Company is party to a number of legal and/or regulatory actions arising out of the normal course of its business. The Company records a loss contingency liability when, in the opinion of management after seeking legal advice, a loss is considered probable and the amount can be reasonably estimated. Based on information currently available and management’s evaluation of such information, the Company does not believe that the resolution of any existing legal or regulatory action is expected to have a material adverse effect on the Company’s financial condition, results of operations or cash flows. The Company’s legal costs associated with defending itself are recorded to expense as incurred. ​ Certain operations of the Company are subject to environmental laws and regulations that govern the discharge of pollutants into the air and water, as well as the handling and disposal of solid and hazardous wastes. The Company believes that its operations are currently in substantial compliance with applicable environmental laws and regulations and that the costs of continuing compliance will not have a material adverse effect on the Company’s financial condition, results of operations or cash flows.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ 548.7	$ 439.2

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Mar. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Basis of Presentation and Pri_2

Basis of Presentation and Principles of Consolidation (Policy)	3 Months Ended
	Mar. 31, 2024
Basis of Presentation and Principles of Consolidation
Principles of Consolidation	The Condensed Consolidated Balance Sheets as of March 31, 2024 and December 31, 2023, and each of the related Condensed Consolidated Statements of Income, Condensed Consolidated Statements of Comprehensive Income and Condensed Consolidated Statements of Cash Flow for the three months ended March 31, 2024 and 2023, include the accounts of Amphenol Corporation and its subsidiaries (“Amphenol,” the “Company,” “we,” “our” or “us”). All material intercompany balances and transactions have been eliminated in consolidation. The condensed consolidated financial statements included herein are unaudited. In the opinion of management, the condensed consolidated financial statements reflect all adjustments, including normal recurring adjustments considered necessary for a fair presentation of the results, in conformity with accounting principles generally accepted in the United States of America. The results of operations for the three months ended March 31, 2024 are not necessarily indicative of the results to be expected for the full year. These condensed consolidated financial statements and the related notes should be read in conjunction with the consolidated financial statements and notes included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2023 (the “2023 Annual Report”).

Inventories (Tables)

Inventories (Tables)	3 Months Ended
	Mar. 31, 2024
Inventories
Schedule of Inventories	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ 2024 2023 Raw materials and supplies $ 970.9 $ 964.7 ​ Work in process ​ 587.0 ​ 562.3 ​ Finished goods ​ 595.0 ​ 640.1 ​ ​ $ 2,152.9 $ 2,167.1 ​ ​

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 31, 2024
Debt
Schedule of debt	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2024 ​ December 31, 2023 ​ ​ ​ ​ Carrying ​ Approximate ​ Carrying ​ Approximate ​ ​ ​ Amount Fair Value Amount Fair Value Revolving Credit Facility ​ ​ ​ $ — $ — $ — $ — ​ U.S. Commercial Paper Program ​ ​ ​ — ​ — ​ — ​ — ​ Euro Commercial Paper Program ​ ​ ​ — ​ — ​ — ​ — ​ Term Loan Credit Facility ​ ​ ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ 3.20% Senior Notes due April 2024 ​ ​ ​ 350.0 ​ 349.9 ​ 350.0 ​ 348.4 ​ 2.050% Senior Notes due March 2025 ​ ​ ​ ​ 399.9 ​ ​ 387.7 ​ ​ 399.8 ​ ​ 386.8 ​ 4.750% Senior Notes due March 2026 ​ ​ ​ ​ 349.2 ​ ​ 347.5 ​ ​ 349.1 ​ ​ 350.6 ​ 0.750% Euro Senior Notes due May 2026 ​ ​ ​ ​ 539.3 ​ ​ 509.7 ​ ​ 551.7 ​ ​ 523.4 ​ 2.000% Euro Senior Notes due October 2028 ​ ​ ​ ​ 538.9 ​ ​ 515.1 ​ ​ 551.4 ​ ​ 531.4 ​ 4.350% Senior Notes due June 2029 ​ ​ ​ ​ 499.8 ​ ​ 486.9 ​ ​ 499.8 ​ ​ 497.2 ​ 2.800% Senior Notes due February 2030 ​ ​ ​ ​ 899.6 ​ ​ 804.2 ​ ​ 899.6 ​ ​ 817.6 ​ 2.200% Senior Notes due September 2031 ​ ​ ​ ​ 748.0 ​ ​ 620.6 ​ ​ 747.9 ​ ​ 629.9 ​ Other debt ​ ​ ​ 7.2 ​ 7.2 ​ 9.5 ​ 9.5 ​ Less: unamortized deferred debt issuance costs ​ ​ (22.5) ​ — ​ (21.5) ​ — ​ Total debt ​ ​ ​ 4,309.4 ​ 4,028.8 ​ 4,337.3 ​ 4,094.8 ​ Less: current portion ​ ​ ​ 752.5 ​ ​ 740.2 ​ 353.8 ​ 352.2 ​ Total long-term debt ​ ​ ​ $ 3,556.9 $ 3,288.6 $ 3,983.5 $ 3,742.6 ​ ​

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2024
Fair Value Measurements
Fair values of financial and non-financial assets and liabilities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements ​ ​ ​ ​ ​ Quoted Prices in ​ Significant ​ Significant ​ ​ ​ ​ ​ Active Markets ​ Observable ​ Unobservable ​ ​ ​ ​ ​ for Identical ​ Inputs ​ Inputs ​ ​ Total ​ Assets (Level 1) ​ (Level 2) ​ (Level 3) March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Short-term investments ​ $ 106.4 ​ $ — ​ $ 106.4 ​ $ — Long-term investments ​ ​ 0.4 ​ ​ — ​ ​ 0.4 ​ ​ — Forward contracts ​ ​ (0.2) ​ ​ — ​ ​ (0.2) ​ ​ — Redeemable noncontrolling interests ​ ​ (30.9) ​ ​ — ​ ​ — ​ ​ (30.9) Total ​ $ 75.7 ​ $ — ​ $ 106.6 ​ $ (30.9) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Short-term investments ​ $ 185.2 ​ $ — ​ $ 185.2 ​ $ — Long-term investments ​ ​ 0.4 ​ ​ — ​ ​ 0.4 ​ ​ — Forward contracts ​ ​ (0.5) ​ ​ — ​ ​ (0.5) ​ ​ — Redeemable noncontrolling interests ​ ​ (30.7) ​ ​ — ​ ​ — ​ ​ (30.7) Total ​ $ 154.4 ​ $ — ​ $ 185.1 ​ $ (30.7)

Income Taxes (Tables)

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2024
Income Taxes
Schedule of provision for income taxes and effective tax rate	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, ​ ​ 2024 ​ 2023 ​ Provision for income taxes ​ $ (110.7) ​ $ (117.2) ​ Effective tax rate ​ 16.7 % 20.9 %

Stockholders' Equity and Nonc_2

Stockholders' Equity and Noncontrolling Interests (Tables)	3 Months Ended
	Mar. 31, 2024
Stockholders' Equity and Noncontrolling Interests
Rollforward of consolidated changes in equity	A rollforward of consolidated changes in equity and redeemable noncontrolling interests for the three months ended March 31, 2024 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Stockholders’ equity attributable to Amphenol Corporation ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ ​ ​ ​ ​ ​ Redeemable ​ Common Stock ​ Treasury Stock ​ Additional ​ ​ ​ ​ Other ​ Non- ​ ​ ​ ​ Non- ​ Shares ​ ​ ​ ​ Shares ​ ​ ​ ​ Paid-In ​ Retained ​ Comprehensive ​ controlling ​ Total ​ controlling ​ (in millions) Amount (in millions) Amount Capital Earnings Loss Interests (1) Equity Interests ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance as of December 31, 2023 600.6 $ 0.6 (1.7) $ (142.8) $ 3,101.2 $ 5,921.1 $ (533.6) $ 49.3 $ 8,395.8 $ 30.7 Net income ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 548.7 ​ ​ ​ ​ 2.9 ​ 551.6 ​ ​ 0.4 Other comprehensive income (loss) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (69.3) ​ (0.8) ​ (70.1) ​ ​ (0.2) Capital contributions from noncontrolling interests ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 0.8 ​ 0.8 ​ ​ ​ Purchase of treasury stock ​ ​ ​ ​ ​ (1.4) ​ (153.8) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (153.8) ​ ​ ​ Retirement of treasury stock (1.4) ​ ​ — ​ 1.4 ​ 153.8 ​ ​ ​ ​ (153.8) ​ ​ ​ ​ ​ ​ ​ — ​ ​ ​ Stock options exercised 2.8 ​ ​ — ​ 0.4 ​ ​ 39.0 ​ 99.1 ​ ​ (20.4) ​ ​ ​ ​ ​ ​ ​ 117.7 ​ ​ ​ Dividends declared ($0.22 per common share) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (132.1) ​ ​ ​ ​ ​ ​ ​ (132.1) ​ ​ ​ Stock-based compensation expense ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 23.8 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 23.8 ​ ​ ​ Balance as of March 31, 2024 602.0 ​ $ 0.6 ​ (1.3) ​ $ (103.8) ​ $ 3,224.1 ​ $ 6,163.5 ​ $ (602.9) ​ $ 52.2 ​ $ 8,733.7 ​ $ 30.9 (1) Excludes redeemable noncontrolling interests. ​ A rollforward of consolidated changes in equity and redeemable noncontrolling interests for the three months ended March 31, 2023 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Stockholders’ equity attributable to Amphenol Corporation ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ ​ ​ ​ ​ ​ Redeemable ​ Common Stock ​ Treasury Stock ​ Additional ​ ​ ​ ​ Other ​ Non- ​ ​ ​ ​ Non- ​ Shares ​ ​ ​ ​ Shares ​ ​ ​ ​ Paid-In ​ Retained ​ Comprehensive ​ controlling ​ Total ​ controlling ​ (in millions) Amount (in millions) Amount Capital Earnings Loss Interests (1) Equity Interests ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance as of December 31, 2022 596.0 $ 0.6 (1.2) $ (79.8) $ 2,650.4 $ 4,979.4 $ (535.0) $ 57.9 $ 7,073.5 $ 20.6 Net income ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 439.2 ​ ​ ​ ​ 3.2 ​ 442.4 ​ 0.3 Other comprehensive income (loss) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 42.4 ​ 0.8 ​ 43.2 ​ — Acquisitions resulting in noncontrolling interests ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 0.8 ​ 0.8 ​ ​ Distributions to shareholders of noncontrolling interests ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (5.2) ​ (5.2) ​ ​ Purchase of treasury stock ​ ​ ​ ​ ​ (2.1) ​ (166.9) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (166.9) ​ ​ Retirement of treasury stock (2.1) ​ ​ — ​ 2.1 ​ 166.9 ​ ​ ​ ​ (166.9) ​ ​ ​ ​ ​ ​ ​ — ​ ​ Stock options exercised 2.4 ​ ​ — ​ 0.2 ​ ​ 10.1 ​ 76.4 ​ ​ (5.4) ​ ​ ​ ​ ​ ​ ​ 81.1 ​ ​ Dividends declared ($0.21 per common share) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (125.0) ​ ​ ​ ​ ​ ​ ​ (125.0) ​ ​ Stock-based compensation expense ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 21.7 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 21.7 ​ ​ Balance as of March 31, 2023 596.3 ​ $ 0.6 ​ (1.0) ​ $ (69.7) ​ $ 2,748.5 ​ $ 5,121.3 ​ $ (492.6) ​ $ 57.5 ​ $ 7,365.6 ​ $ 20.9 (1) Excludes redeemable noncontrolling interests. ​ ​
Schedules of dividends	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2024 ​ 2023 ​ Dividends declared ​ $ 132.1 ​ $ 125.0 ​ Dividends paid (including those declared in the prior year) ​ 131.7 ​ 124.9 ​

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2024
Stock-Based Compensation
Schedule of stock option activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ Average ​ Aggregate ​ ​ ​ Weighted ​ Remaining ​ Intrinsic ​ ​ ​ Average ​ Contractual ​ Value ​ ​ Options Exercise Price Term (in years) (in millions) Options outstanding at January 1, 2024 60,390,162 ​ $ 50.45 5.81 ​ $ 2,939.5 ​ Options granted 58,031 ​ 90.72 ​ ​ ​ ​ ​ ​ Options exercised (3,156,425) ​ 37.27 ​ ​ ​ ​ ​ ​ Options forfeited (43,137) ​ 65.02 ​ ​ ​ ​ ​ ​ Options outstanding at March 31, 2024 57,248,631 ​ $ 51.21 5.69 ​ $ 3,671.9 ​ Vested and non-vested options expected to vest at March 31, 2024 55,794,585 ​ $ 50.80 5.63 ​ $ 3,601.3 ​ Exercisable options at March 31, 2024 34,849,870 ​ $ 43.54 4.53 ​ $ 2,502.7 ​
Summary of status of non-vested options and changes during the year	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ Average ​ ​ ​ ​ ​ Fair Value at ​ ​ ​ Options ​ Grant Date Non-vested options at January 1, 2024 22,523,981 ​ $ 14.57 ​ Options granted 58,031 ​ 26.36 ​ Options vested (146,726) ​ 15.79 ​ Options forfeited (36,525) ​ 17.73 ​ Non-vested options at March 31, 2024 22,398,761 ​ $ 14.58 ​
Summary of activity in the option plans	​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ March 31, ​ 2024 ​ 2023 Total intrinsic value of stock options exercised $ 215.8 ​ $ 125.7 Total fair value of stock options vested 2.3 ​ 2.3

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2024
Earnings Per Share
Schedule of the reconciliation of basic weighted average common shares outstanding to diluted weighted average common shares outstanding	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, (dollars and shares in millions, except per share data) 2024 2023 Net income attributable to Amphenol Corporation stockholders ​ $ 548.7 ​ $ 439.2 ​ ​ ​ ​ ​ ​ ​ Weighted average common shares outstanding — Basic ​ 600.0 ​ 595.1 Effect of dilutive stock options ​ 27.9 ​ 24.8 Weighted average common shares outstanding — Diluted ​ 627.9 ​ 619.9 ​ ​ ​ ​ ​ ​ ​ Net income attributable to Amphenol Corporation per common share — Basic ​ $ 0.91 ​ $ 0.74 ​ ​ ​ ​ ​ ​ ​ Net income attributable to Amphenol Corporation per common share — Diluted ​ $ 0.87 ​ $ 0.71

Benefit Plans and Other Postr_2

Benefit Plans and Other Postretirement Benefits (Tables)	3 Months Ended
	Mar. 31, 2024
Benefit Plans and Other Postretirement Benefits
Schedule of components of net pension expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2024 2023 Service cost $ 1.0 ​ $ 1.9 Interest cost ​ 6.1 ​ 6.5 Expected return on plan assets ​ (7.2) ​ (7.3) Amortization of prior service cost ​ 0.3 ​ 0.4 Amortization of net actuarial losses ​ 1.0 ​ 0.6 Net pension expense $ 1.2 ​ $ 2.1

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2024
Goodwill and Other Intangible Assets
Schedule of changes in the carrying amount of goodwill by segment	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Harsh ​ ​ Interconnect ​ ​ ​ ​ Environment ​ Communications ​ and Sensor ​ ​ ​ ​ ​ Solutions ​ Solutions ​ Systems ​ Total Goodwill at December 31, 2023 ​ $ 2,009.3 ​ $ 2,977.5 ​ $ 2,105.6 ​ $ 7,092.4 ​ Acquisition-related ​ 1.2 ​ 4.5 ​ 43.7 ​ 49.4 ​ Foreign currency translation ​ (9.2) ​ (9.5) ​ (22.6) ​ (41.3) ​ Goodwill at March 31, 2024 ​ $ 2,001.3 ​ $ 2,972.5 ​ $ 2,126.7 ​ $ 7,100.5 ​
Summary of the Company's amortizable intangible assets	Other than goodwill noted above, the Company’s intangible assets as of March 31, 2024 and December 31, 2023 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2024 ​ December 31, 2023 ​ Weighted ​ Gross ​ Net Gross ​ Net ​ Average ​ Carrying ​ Accumulated ​ Carrying ​ Carrying ​ Accumulated ​ Carrying ​ Life (years) ​ Amount ​ Amortization ​ Amount ​ Amount ​ Amortization ​ Amount Customer relationships 10 ​ $ 780.2 ​ $ 462.5 ​ $ 317.7 ​ $ 782.6 ​ $ 450.6 ​ $ 332.0 Proprietary technology 13 ​ 350.8 ​ 152.2 ​ ​ 198.6 ​ 365.1 ​ 146.1 ​ ​ 219.0 Backlog and other 1 ​ 99.4 ​ 99.4 ​ ​ — ​ 114.1 ​ 99.4 ​ ​ 14.7 Total intangible assets (definite-lived) 10 ​ ​ 1,230.4 ​ ​ 714.1 ​ ​ 516.3 ​ ​ 1,261.8 ​ ​ 696.1 ​ ​ 565.7 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Trade names (indefinite-lived) ​ ​ ​ 269.1 ​ ​ ​ ​ ​ 269.1 ​ ​ 269.1 ​ ​ ​ ​ ​ 269.1 ​ ​ ​ $ 1,499.5 ​ $ 714.1 ​ $ 785.4 ​ $ 1,530.9 ​ $ 696.1 ​ $ 834.8
Summary of the Company's indefinite-lived intangible assets	Other than goodwill noted above, the Company’s intangible assets as of March 31, 2024 and December 31, 2023 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2024 ​ December 31, 2023 ​ Weighted ​ Gross ​ Net Gross ​ Net ​ Average ​ Carrying ​ Accumulated ​ Carrying ​ Carrying ​ Accumulated ​ Carrying ​ Life (years) ​ Amount ​ Amortization ​ Amount ​ Amount ​ Amortization ​ Amount Customer relationships 10 ​ $ 780.2 ​ $ 462.5 ​ $ 317.7 ​ $ 782.6 ​ $ 450.6 ​ $ 332.0 Proprietary technology 13 ​ 350.8 ​ 152.2 ​ ​ 198.6 ​ 365.1 ​ 146.1 ​ ​ 219.0 Backlog and other 1 ​ 99.4 ​ 99.4 ​ ​ — ​ 114.1 ​ 99.4 ​ ​ 14.7 Total intangible assets (definite-lived) 10 ​ ​ 1,230.4 ​ ​ 714.1 ​ ​ 516.3 ​ ​ 1,261.8 ​ ​ 696.1 ​ ​ 565.7 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Trade names (indefinite-lived) ​ ​ ​ 269.1 ​ ​ ​ ​ ​ 269.1 ​ ​ 269.1 ​ ​ ​ ​ ​ 269.1 ​ ​ ​ $ 1,499.5 ​ $ 714.1 ​ $ 785.4 ​ $ 1,530.9 ​ $ 696.1 ​ $ 834.8

Reportable Business Segments (T

Reportable Business Segments (Tables)	3 Months Ended
	Mar. 31, 2024
Reportable Business Segments
Schedule of net sales, both external and intersegment, by segment	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ External ​ Intersegment Three Months Ended March 31, ​ 2024 ​ 2023 ​ 2024 ​ 2023 Harsh Environment Solutions $ 916.0 ​ $ 854.2 ​ $ 19.6 ​ $ 23.8 Communications Solutions ​ ​ 1,265.7 ​ ​ 1,126.7 ​ ​ 11.2 ​ ​ 13.9 Interconnect and Sensor Systems ​ ​ 1,074.6 ​ ​ 993.1 ​ ​ 5.1 ​ ​ 5.1 Consolidated Net sales ​ $ 3,256.3 ​ $ 2,974.0 ​ $ 35.9 ​ $ 42.8
Schedule of the reconciliation of segment operating income to consolidated income before income taxes	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2024 ​ 2023 Segment operating income: ​ ​ ​ ​ ​ ​ Harsh Environment Solutions ​ $ 244.4 ​ $ 226.3 Communications Solutions ​ ​ 286.2 ​ ​ 230.6 Interconnect and Sensor Systems ​ ​ 195.4 ​ ​ 178.8 Total segment operating income ​ ​ 726.0 ​ ​ 635.7 ​ ​ ​ ​ ​ ​ ​ Corporate / Other: ​ ​ ​ ​ ​ ​ Stock-based compensation expense ​ ​ (23.8) ​ ​ (21.7) Acquisition-related expenses ​ ​ — ​ ​ (5.4) Other operating expenses ​ ​ (17.4) ​ ​ (16.9) Interest expense ​ ​ (38.1) ​ ​ (35.9) Other income (expense), net ​ ​ 16.0 ​ ​ 4.1 ​ ​ ​ ​ ​ ​ ​ Income before income taxes ​ $ 662.7 ​ $ 559.9
Schedule of depreciation and amortization expense	​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2024 ​ 2023 Harsh Environment Solutions $ 22.7 ​ $ 24.5 Communications Solutions ​ ​ 45.1 ​ ​ 39.2 Interconnect and Sensor Systems ​ ​ 33.9 ​ ​ 31.0 Corporate / Other ​ ​ 2.1 ​ ​ 1.6 Total ​ $ 103.8 ​ $ 96.3 ​

Revenue Recognition (Tables)

Revenue Recognition (Tables)	3 Months Ended
	Mar. 31, 2024
Revenue Recognition
Schedule of disaggregation of net sales	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Harsh ​ ​ ​ ​ ​ ​ ​ ​ Environment ​ Communications ​ Interconnect and ​ Total Reportable ​ ​ Solutions ​ Solutions ​ Sensor Systems ​ Business Segments Three Months Ended March 31, 2024 2023 2024 2023 2024 2023 ​ 2024 2023 Net sales by: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Sales channel: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ End customers and contract manufacturers ​ $ 675.3 $ 623.8 $ 990.9 $ 890.8 $ 1,032.0 $ 950.5 ​ $ 2,698.2 $ 2,465.1 Distributors and resellers ​ 240.7 ​ 230.4 ​ 274.8 ​ 235.9 ​ 42.6 ​ 42.6 ​ 558.1 ​ 508.9 ​ ​ $ 916.0 ​ $ 854.2 ​ $ 1,265.7 ​ $ 1,126.7 ​ $ 1,074.6 ​ $ 993.1 ​ $ 3,256.3 ​ $ 2,974.0 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ United States ​ $ 455.1 ​ $ 418.8 ​ $ 346.6 ​ $ 336.2 ​ $ 311.4 ​ $ 297.3 ​ $ 1,113.1 ​ $ 1,052.3 China ​ 81.0 ​ 86.3 ​ 374.2 ​ 350.0 ​ 215.2 ​ 182.8 ​ ​ 670.4 ​ ​ 619.1 Other foreign locations ​ 379.9 ​ 349.1 ​ 544.9 ​ 440.5 ​ 548.0 ​ 513.0 ​ 1,472.8 ​ ​ 1,302.6 ​ ​ $ 916.0 ​ $ 854.2 ​ $ 1,265.7 ​ $ 1,126.7 ​ $ 1,074.6 ​ $ 993.1 ​ $ 3,256.3 ​ $ 2,974.0 ​

Inventories (Details)

Inventories (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Inventories
Raw materials and supplies	$ 970.9	$ 964.7
Work in process	587	562.3
Finished goods	595	640.1
Inventories	$ 2,152.9	$ 2,167.1

Debt, Schedule of Debt (Details

Debt, Schedule of Debt (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023	Mar. 30, 2023
Debt
Less: unamortized deferred debt issuance costs	$ (22.5)	$ (21.5)
Total debt	4,309.4	4,337.3
Less current portion	752.5	353.8
Total long-term debt	3,556.9	3,983.5
Total debt, Approximate Fair Value	4,028.8	4,094.8
Less current portion, Fair Value	740.2	352.2
Long-term debt, Approximate Fair Value	3,288.6	3,742.6
Fair Value
Debt
Less: unamortized deferred debt issuance costs
The "Revolving Credit Facility" | Revolving Credit Facility
Debt
Debt carrying amount, net of unamortized discount or premium before deferred debt issuance costs	0	0
Total debt, Approximate Fair Value	0	0
U.S. Commercial Paper Program
Debt
Debt carrying amount, net of unamortized discount or premium before deferred debt issuance costs	0	0
Total debt, Approximate Fair Value	0	0
Euro Commercial Paper Program
Debt
Debt carrying amount, net of unamortized discount or premium before deferred debt issuance costs	0	0
Total debt, Approximate Fair Value	0	0
2022 Term Loan
Debt
Debt carrying amount, net of unamortized discount or premium before deferred debt issuance costs	0	0
Total debt, Approximate Fair Value	$ 0	$ 0
3.20% Senior Notes due April 2024
Debt
Stated interest rate (as a percent)	3.20%	3.20%
Debt carrying amount, net of unamortized discount or premium before deferred debt issuance costs	$ 350	$ 350
Total debt, Approximate Fair Value	$ 349.9	$ 348.4
2.05% Senior Notes due March 2025
Debt
Stated interest rate (as a percent)	2.05%	2.05%
Debt carrying amount, net of unamortized discount or premium before deferred debt issuance costs	$ 399.9	$ 399.8
Total debt, Approximate Fair Value	$ 387.7	$ 386.8
4.750% Senior Notes due March 2026
Debt
Stated interest rate (as a percent)	4.75%	4.75%	4.75%
Debt carrying amount, net of unamortized discount or premium before deferred debt issuance costs	$ 349.2	$ 349.1
Total debt, Approximate Fair Value	$ 347.5	$ 350.6
0.750% Euro Senior Notes due May 2026
Debt
Stated interest rate (as a percent)	0.75%	0.75%
Debt carrying amount, net of unamortized discount or premium before deferred debt issuance costs	$ 539.3	$ 551.7
Total debt, Approximate Fair Value	$ 509.7	$ 523.4
2.000% Euro Senior Notes due October 2028
Debt
Stated interest rate (as a percent)	2%	2%
Debt carrying amount, net of unamortized discount or premium before deferred debt issuance costs	$ 538.9	$ 551.4
Total debt, Approximate Fair Value	$ 515.1	$ 531.4
4.350% Senior Notes due June 2029
Debt
Stated interest rate (as a percent)	4.35%	4.35%
Debt carrying amount, net of unamortized discount or premium before deferred debt issuance costs	$ 499.8	$ 499.8
Total debt, Approximate Fair Value	$ 486.9	$ 497.2
2.800% Senior Notes due February 2030
Debt
Stated interest rate (as a percent)	2.80%	2.80%
Debt carrying amount, net of unamortized discount or premium before deferred debt issuance costs	$ 899.6	$ 899.6
Total debt, Approximate Fair Value	$ 804.2	$ 817.6
2.200% Senior Notes due September 2031
Debt
Stated interest rate (as a percent)	2.20%	2.20%
Debt carrying amount, net of unamortized discount or premium before deferred debt issuance costs	$ 748	$ 747.9
Total debt, Approximate Fair Value	620.6	629.9
Other Debt
Debt
Debt carrying amount, net of unamortized discount or premium before deferred debt issuance costs	7.2	9.5
Total debt, Approximate Fair Value	$ 7.2	$ 9.5

Debt, Revolving Credit Facility

Debt, Revolving Credit Facility (Details) - The "Revolving Credit Facility" - USD ($) $ in Millions		3 Months Ended
	Mar. 21, 2024	Mar. 31, 2024	Mar. 20, 2024	Dec. 31, 2023
Debt
Maximum borrowing capacity	$ 3,000		$ 2,500
Borrowings under the Revolving Credit Facility		$ 0		$ 0
Increase in aggregate commitments	$ 500
Debt instrument, covenant compliance		On March 31, 2024, the Company was in compliance with the financial covenants under the Revolving Credit Facility

Debt, Term Loan Credit Facility

Debt, Term Loan Credit Facility (Details) - 2022 Term Loan $ in Millions		3 Months Ended
	Apr. 19, 2022 USD ($) agreement	Mar. 31, 2024 USD ($)
Debt
Maximum borrowing capacity	$ 750
Borrowings under the unsecured term loan credit facility		$ 0
Maturity term	2 years
Debt maturity date	Apr. 19, 2024
Number of occasions allowed to borrow over the life of the facility | agreement	5
Credit facility, covenant compliance		On March 31, 2024, the Company was in compliance with the financial covenants under the Term Loan.

Debt, Commercial Paper (Details

Debt, Commercial Paper (Details) $ in Millions		3 Months Ended
	Mar. 21, 2024 USD ($)	Mar. 31, 2024 USD ($) item	Dec. 31, 2023 USD ($)
Commercial Paper Programs and Revolving Credit Facility [Member]
Debt
Maximum borrowing capacity		$ 3,000
U.S. Commercial Paper Program
Debt
Debt carrying amount, net of unamortized discount before deferred debt issuance costs		0	$ 0
Maximum borrowing capacity		$ 3,000
Increase in aggregate commitments	$ 500
U.S. Commercial Paper Program | Maximum
Debt
Maturity term		397 days
Euro Commercial Paper Program
Debt
Number of wholly-owned subsidiaries that entered into a euro-commercial paper program | item		1
Debt carrying amount, net of unamortized discount before deferred debt issuance costs		$ 0	$ 0
Maximum borrowing capacity		$ 2,000
Euro Commercial Paper Program | Maximum
Debt
Maturity term		183 days

Debt, U.S. Senior Notes (Detail

Debt, U.S. Senior Notes (Details) $ in Millions				3 Months Ended
	Apr. 05, 2024 USD ($) loan	Apr. 01, 2024 USD ($)	Mar. 30, 2023 USD ($)	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2023
Debt
Repayments of long-term debt				$ 1.1	$ 3.1
U.S. Senior Notes
Debt
Redemption price as a percentage of principal amount				100%
3.20% Senior Notes due April 2024
Debt
Stated interest rate (as a percent)				3.20%		3.20%
3.20% Senior Notes due April 2024 | Subsequent Event
Debt
Stated interest rate (as a percent)		3.20%
Repayments of Senior Notes		$ 350
4.750% Senior Notes due March 2026
Debt
Redemption price as a percentage of principal amount			100%
Debt instrument, principal amount			$ 350
Stated interest rate (as a percent)			4.75%	4.75%		4.75%
Debt instrument, face amount, net of discount (as a percent)			99.658%
Debt maturity date				Mar. 30, 2026
New Senior Notes [Member] | Subsequent Event
Debt
Number of series of unsecured senior notes issued | loan	3
Redemption price as a percentage of principal amount	100%
New Senior Notes [Member] | Pending Acquisition Not Consummated By Agreement Date [Member] | Subsequent Event
Debt
Redemption price as a percentage of principal amount	101%
5.050% Senior Notes due April 2027 | Subsequent Event
Debt
Debt instrument, principal amount	$ 450
Stated interest rate (as a percent)	5.05%
Debt instrument, face amount, net of discount (as a percent)	99.887%
Debt maturity date	Apr. 05, 2027
5.050% Senior Notes due April 2027 | Prior To March 5 2027 [Member] | Subsequent Event
Debt
Redemption price as a percentage of principal amount	100%
5.050% Senior Notes due April 2029 | Subsequent Event
Debt
Debt instrument, principal amount	$ 450
Stated interest rate (as a percent)	5.05%
Debt instrument, face amount, net of discount (as a percent)	99.90%
Debt maturity date	Apr. 05, 2029
5.050% Senior Notes due April 2029 | Prior To March 5 2029 [Member] | Subsequent Event
Debt
Redemption price as a percentage of principal amount	100%
5.250% Senior Notes due April 2034 | Subsequent Event
Debt
Debt instrument, principal amount	$ 600
Stated interest rate (as a percent)	5.25%
Debt instrument, face amount, net of discount (as a percent)	99.90%
Debt maturity date	Apr. 05, 2034
5.250% Senior Notes due April 2034 | Prior To January 5 2034 [Member] | Subsequent Event
Debt
Redemption price as a percentage of principal amount	100%
Euro Senior Notes and US Senior Notes [Member]
Debt
Debt instrument, covenant compliance				On March 31, 2024, the Company was in compliance with all requirements under its Senior Notes

Debt, Euro Senior Notes (Detail

Debt, Euro Senior Notes (Details) € in Millions	3 Months Ended
	Mar. 31, 2024 EUR (€) loan
Euro Notes [Member]
Debt
Number of outstanding notes | loan	2
Redemption price as a percentage of principal amount	100%
0.750% Euro Senior Notes Due May 2026 [Member]
Debt
Debt instrument, principal amount	€ 500
Stated interest rate (as a percent)	0.75%
Debt maturity date	May 04, 2026
Debt instrument, face amount, net of discount (as a percent)	99.563%
2.000% Euro Senior Notes due October 2028 [Member]
Debt
Debt instrument, principal amount	€ 500
Stated interest rate (as a percent)	2%
Debt maturity date	Oct. 08, 2028
Debt instrument, face amount, net of discount (as a percent)	99.498%
Euro Senior Notes and US Senior Notes [Member]
Debt
Debt instrument, covenant compliance	On March 31, 2024, the Company was in compliance with all requirements under its Senior Notes

Fair Value Measurements (Detail

Fair Value Measurements (Details) $ in Millions	Mar. 31, 2024 USD ($) contract	Dec. 31, 2023 USD ($) contract
Net Investment Hedging [Member]
Fair value of assets and liabilities measured on recurring basis
Number of forward contracts | contract	0	0
Cash Flow Hedging
Fair value of assets and liabilities measured on recurring basis
Number of forward contracts | contract	0	0
Fair value measurements recurring basis
Fair value of assets and liabilities measured on recurring basis
Short-term investments	$ 106.4	$ 185.2
Long-term investments	0.4	0.4
Forward contracts	(0.2)	(0.5)
Redeemable noncontrolling interests	(30.9)	(30.7)
Total asset	75.7	154.4
Fair value measurements recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair value of assets and liabilities measured on recurring basis
Short-term investments	0	0
Long-term investments	0	0
Forward contracts	0	0
Redeemable noncontrolling interests	0	0
Total asset	0	0
Fair value measurements recurring basis | Significant Observable Inputs (Level 2)
Fair value of assets and liabilities measured on recurring basis
Short-term investments	106.4	185.2
Long-term investments	0.4	0.4
Forward contracts	(0.2)	(0.5)
Redeemable noncontrolling interests	0	0
Total asset	106.6	185.1
Fair value measurements recurring basis | Significant Unobservable Inputs (Level 3)
Fair value of assets and liabilities measured on recurring basis
Short-term investments	0	0
Long-term investments	0	0
Forward contracts	0	0
Redeemable noncontrolling interests	(30.9)	(30.7)
Total liability	$ (30.9)	$ (30.7)

Income Taxes, Provision and Eff

Income Taxes, Provision and Effective tax rate (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Taxes
Provision for income taxes	$ (110.7)	$ (117.2)
Effective tax rate	16.70%	20.90%
Discrete tax benefit comprised of the settlement of tax audits and lapses of statutes of limitation, along with a difference in a non-U.S. tax filing position	$ 18.6
Impact on the effective tax rate associated with the discrete tax benefit comprised of the settlement of tax audits and lapses of statutes of limitation, along with a difference in a non-U.S. tax filing position.	(2.80%)
Excess tax benefit from option exercises	$ 29.7	$ 17.1
Excess tax benefit, impact on effective tax rate	(4.50%)	(3.10%)

Income Taxes, Unrecognized tax

Income Taxes, Unrecognized tax benefits (Details) $ in Millions	Mar. 31, 2024 USD ($)
Income Taxes
Unrecognized tax benefits, anticipated adjustment for changing facts and circumstances, over the next twelve month period	$ 24.8
Amount for unrecognized tax benefits, including penalties and interest, which if recognized would impact the effective tax rate	$ 201.5

Stockholders Equity and Noncont

Stockholders Equity and Noncontrolling Interests (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions			3 Months Ended
	Oct. 24, 2023	Oct. 23, 2023	Mar. 31, 2024	Mar. 31, 2023
Increase (Decrease) In Equity
Balance at beginning of period			$ 8,395.8	$ 7,073.5
Redeemable noncontrolling interest, balance at beginning of period			30.7
Net income, excluding portion attributable to redeemable noncontrolling interest			551.6	442.4
Net income			552	442.7
Other comprehensive income (loss), excluding portion attributable to redeemable noncontrolling interests			(70.1)	43.2
Increase in noncontrolling interests associated with capital contributions			0.8
Acquisitions resulting in noncontrolling interest				0.8
Distributions to shareholders of noncontrolling interests				(5.2)
Purchase of treasury stock			(153.8)	(166.9)
Retirement of treasury stock			0	0
Stock options exercised			117.7	81.1
Dividends declared			(132.1)	(125)
Stock-based compensation expense			23.8	21.7
Balance at end of period			8,733.7	$ 7,365.6
Redeemable noncontrolling interest, balance at end of period			$ 30.9
Dividends [Abstract]
Dividends declared per share (in dollars per share)	$ 0.22	$ 0.21	$ 0.22	$ 0.21
Redeemable Non-Controlling Interest [Member]
Increase (Decrease) In Equity
Redeemable noncontrolling interest, balance at beginning of period			$ 30.7	$ 20.6
Net income, redeemable non-controlling interest			0.4	0.3
Redeemable noncontrolling interest, other comprehensive income loss net of tax			(0.2)	0
Redeemable noncontrolling interest, balance at end of period			$ 30.9	$ 20.9
Common Stock
Increase (Decrease) In Equity
Balance (in shares)			600.6	596
Balance at beginning of period			$ 0.6	$ 0.6
Retirement of treasury stock			$ 0	$ 0
Retirement of treasury stock (in shares)			(1.4)	(2.1)
Stock options exercised			$ 0	$ 0
Stock options exercised (in shares)			2.8	2.4
Balance (in shares)			602	596.3
Balance at end of period			$ 0.6	$ 0.6
Treasury Stock
Increase (Decrease) In Equity
Balance (in shares)			(1.7)	(1.2)
Balance at beginning of period			$ (142.8)	$ (79.8)
Purchase of treasury stock			$ (153.8)	$ (166.9)
Purchase of treasury stock (in shares)			(1.4)	(2.1)
Retirement of treasury stock			$ 153.8	$ 166.9
Retirement of treasury stock (in shares)			1.4	2.1
Stock options exercised			$ 39	$ 10.1
Stock options exercised (in shares)			0.4	0.2
Balance at end of period			$ (103.8)	$ (69.7)
Balance (in shares)			(1.3)	(1)
Additional Paid in Capital
Increase (Decrease) In Equity
Balance at beginning of period			$ 3,101.2	$ 2,650.4
Stock options exercised			99.1	76.4
Stock-based compensation expense			23.8	21.7
Balance at end of period			3,224.1	2,748.5
Retained Earnings
Increase (Decrease) In Equity
Balance at beginning of period			5,921.1	4,979.4
Net income, excluding portion attributable to redeemable noncontrolling interest			548.7	439.2
Retirement of treasury stock			(153.8)	(166.9)
Stock options exercised			(20.4)	(5.4)
Dividends declared			(132.1)	(125)
Balance at end of period			6,163.5	5,121.3
Accumulated Other Comprehensive Loss
Increase (Decrease) In Equity
Balance at beginning of period			(533.6)	(535)
Other comprehensive income (loss), excluding portion attributable to redeemable noncontrolling interests			(69.3)	42.4
Balance at end of period			(602.9)	(492.6)
Noncontrolling Interests
Increase (Decrease) In Equity
Balance at beginning of period			49.3	57.9
Net income, excluding portion attributable to redeemable noncontrolling interest			2.9	3.2
Other comprehensive income (loss), excluding portion attributable to redeemable noncontrolling interests			(0.8)	0.8
Increase in noncontrolling interests associated with capital contributions			0.8
Acquisitions resulting in noncontrolling interest				0.8
Distributions to shareholders of noncontrolling interests				(5.2)
Balance at end of period			$ 52.2	$ 57.5

Stockholders Equity and Nonco_2

Stockholders Equity and Noncontrolling Interests, Stock Repurchase (Details) - USD ($) shares in Millions, $ in Millions			1 Months Ended	3 Months Ended
	Apr. 23, 2024	Apr. 27, 2021	Apr. 26, 2024	Mar. 31, 2024	Mar. 31, 2023
Stockholders' Equity
Treasury stock retired (in dollars)				$ 0	$ 0
Payments for shares repurchased (in dollars)				$ 153.8	$ 166.9
2021 Stock Repurchase Program
Stockholders' Equity
Value of shares authorized to be repurchased (in dollars)		$ 2,000
Repurchase of stock program, period		3 years
Number of treasury shares retired				1.4	2.1
Treasury stock retired (in dollars)				$ 153.8	$ 166.9
Number of shares repurchased				1.4	2.1
Payments for shares repurchased (in dollars)				$ 153.8	$ 166.9
Subsequent Event | 2021 Stock Repurchase Program
Stockholders' Equity
Number of shares repurchased			0.6
Payments for shares repurchased (in dollars)			$ 71.8
Subsequent Event | 2024 Stock Repurchase Program
Stockholders' Equity
Value of shares authorized to be repurchased (in dollars)	$ 2,000
Repurchase of stock program, period	3 years

Stockholders Equity and Nonco_3

Stockholders Equity and Noncontrolling Interests, Dividends (Details) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended
	Oct. 24, 2023	Oct. 23, 2023	Mar. 31, 2024	Mar. 31, 2023
Stockholders' Equity and Noncontrolling Interests
Dividends declared per share (in dollars per share)	$ 0.22	$ 0.21	$ 0.22	$ 0.21
Dividends declared			$ 132.1	$ 125
Dividends paid (including those declared in the prior year)			$ 131.7	$ 124.9

Stock-Based Compensation, Stock

Stock-Based Compensation, Stock-based Comp Expense (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Stock-Based Compensation
Expense incurred for stock-based compensation plans	$ 23.8	$ 21.7
Recognized tax benefit related to stock-based compensation	32.2	19.3
Excess tax benefit from option exercises	$ 29.7	$ 17.1

Stock-Based Compensation, Sto_2

Stock-Based Compensation, Stock Options (Details) - shares		3 Months Ended
	May 19, 2021	Mar. 31, 2024	May 18, 2021
2009 Employee Option Plan
Stock-Based Compensation
Additional shares available for the granting of stock options		0
Options ratable vesting period		5 years
Options exercisable period		10 years
2017 Option Plan
Stock-Based Compensation
Additional shares available for the granting of stock options	40,000,000
Number of shares originally authorized for issuance of stock options under stock option plan			60,000,000
Remaining shares available for the granting of stock options under plan		31,265,713
Options ratable vesting period		5 years
Options exercisable period		10 years

Stock-Based Compensation, Sto_3

Stock-Based Compensation, Stock Option Activity (Details) - Stock Options - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Stock option activity
Options outstanding at the beginning of the period (in shares)	60,390,162
Non-vested options, options granted (in shares)	58,031
Options exercised (in shares)	(3,156,425)
Options forfeited (in shares)	(43,137)
Options outstanding at the end of the period (in shares)	57,248,631	60,390,162
Vested and non-vested options expected to vest at the end of the period (in shares)	55,794,585
Exercisable at the end of the period (in shares)	34,849,870
Weighted Average Exercise Price
Weighted average exercise price, options outstanding at the beginning of the period (in dollars per share)	$ 50.45
Weighted average exercise price, options granted (in dollars per share)	90.72
Weighted average exercise price, options exercised (in dollars per share)	37.27
Weighted average exercise price, options forfeited (in dollars per share)	65.02
Weighted average exercise price, options outstanding at the end of the period (in dollars per share)	51.21	$ 50.45
Weighted average exercise price, vested and non-vested options expected to vest (in dollars per share)	50.80
Weighted average exercise price, exercisable (in dollars per share)	$ 43.54
Weighted Average Remaining Contractual Term
Weighted average remaining contractual term of options outstanding	5 years 8 months 8 days	5 years 9 months 21 days
Weighted average remaining contractual term of options vested options and non-vested expected to vest	5 years 7 months 17 days
Weighted average remaining contractual term of options exercisable	4 years 6 months 10 days
Aggregate Intrinsic Value
Aggregate intrinsic value of options outstanding	$ 3,671.9	$ 2,939.5
Aggregate intrinsic value of options, vested and non-vested options expected to vest	3,601.3
Aggregate intrinsic value of options exercisable	$ 2,502.7

Stock-Based Compensation, Non-V

Stock-Based Compensation, Non-Vested Stock Option Activity (Details) - Stock Options	3 Months Ended
	Mar. 31, 2024 $ / shares shares
Status of the Company's non-vested options and changes during the year
Non-vested options at the beginning of the period (in shares) | shares	22,523,981
Non-vested options, options granted (in shares) | shares	58,031
Non-vested options, options vested (in shares) | shares	(146,726)
Non-vested options, options forfeited (in shares) | shares	(36,525)
Non-vested options at the end of the period (in shares) | shares	22,398,761
Weighted Average Fair Value at Grant Date
Weighted average fair value at the grant date, Non-vested options at the beginning of the period (in dollars per share) | $ / shares	$ 14.57
Weighted average fair value at grant date, options granted (in dollars per share) | $ / shares	26.36
Weighted average fair value at grant date, options vested (in dollars per share) | $ / shares	15.79
Weighted average fair value at grant date, options forfeited (in dollars per share) | $ / shares	17.73
Weighted average fair value at the grant date, Non-vested options at the end of the period (in dollars per share) | $ / shares	$ 14.58

Stock-Based Compensation, Optio

Stock-Based Compensation, Option Plans (Details) - Stock Options - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Stock-Based Compensation
Total intrinsic value of stock options exercised (in dollars)	$ 215.8	$ 125.7
Total fair value of stock options vested (in dollars)	2.3	$ 2.3
Total compensation cost related to non-vested options not yet recognized (in dollars)	$ 228.1
Weighted average expected amortization period	3 years 2 months 8 days

Stock-Based Compensation, Phant

Stock-Based Compensation, Phantom Stock (Details) - USD ($) $ in Millions		3 Months Ended
	Jun. 05, 2023	Mar. 31, 2024
Phantom stock for non-employee directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of phantom stock granted (in shares)	19,000
Total compensation cost related to non-vested restricted shares not yet recognized (in dollars)		$ 0.2
Weighted average expected amortization period		1 month 13 days
Phantom stock for non-employee directors, Each non-employee director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of phantom stock granted (in shares)	2,375

Earnings Per Share, Reconciliat

Earnings Per Share, Reconciliation (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share
Net Income (Loss)	$ 548.7	$ 439.2
Weighted average common shares outstanding - Basic (in shares)	600	595.1
Effect of dilutive stock options (in shares)	27.9	24.8
Weighted average common shares outstanding - Diluted (in shares)	627.9	619.9
Net income attributable to Amphenol Corporation per common share - Basic:
Net income attributable to Amphenol Corporation per common share - Basic (in dollars per share)	$ 0.91	$ 0.74
Net income attributable to Amphenol Corporation per common share - Diluted:
Net income attributable to Amphenol Corporation per common share - Diluted (in dollars per share)	$ 0.87	$ 0.71
Anti-dilutive common shares
Anti-dilutive stock options, excluded from the computations of earnings per share (in shares)	0.1	7.1

Benefit Plans and Other Postr_3

Benefit Plans and Other Postretirement Benefits, Net pension expense (Details) - Pension Benefits - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Components of net pension expense:
Service cost	$ 1	$ 1.9
Interest cost	6.1	6.5
Expected return on plan assets	(7.2)	(7.3)
Amortization of prior service cost	0.3	0.4
Amortization of net actuarial losses	1	0.6
Net pension (income) expense	1.2	$ 2.1
United States
Defined Benefit Plan Disclosure
Estimated future employer contribution in fiscal year	$ 0

Benefit Plans and Other Postr_4

Benefit Plans and Other Postretirement Benefits, Defined contribution plans (Details) - United States - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Defined Contribution Plans Disclosure
Contributions to U.S. defined contribution plans by the Company, maximum percentage of eligible compensation	7%	7%
Matching contributions to U.S. defined contribution plans by the Company	$ 7	$ 7.5

Acquisitions (Details)

Acquisitions (Details) $ in Millions		3 Months Ended			12 Months Ended
	Jan. 30, 2024 USD ($)	Mar. 31, 2024 USD ($) agreement segment	Jun. 30, 2023 agreement	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($) agreement
Acquisitions
Number of reportable business segments | segment		3
Acquisition-related expenses		$ 0		$ 5.4
Purchase price, net of cash acquired		0		113.2
Bargain purchase gain on acquisition					$ 5.4
Goodwill		7,100.5			$ 7,092.4
Amortization expense		20.4		23.2
Carlisle Interconnect Technologies Acquisition [Member]
Acquisitions
Business acquisition, date of agreement	Jan. 30, 2024
Expected price of acquisition	$ 2,025
2023 Acquisitions [Member]
Acquisitions
Number of acquisitions | agreement					10
Acquisition-related expenses				5.4
Acquisition-related expenses, net of tax				4
Purchase price, net of cash acquired					$ 970.4
Goodwill		658.8
Goodwill deductible for tax purposes		165
Definite-lived intangible assets		$ 153.2
Number of acquisitions for which acquisition accounting has been completed | agreement		1
Customer relationships | 2023 Acquisitions [Member] | Minimum
Acquisitions
Useful lives		6 years
Customer relationships | 2023 Acquisitions [Member] | Maximum
Acquisitions
Useful lives		12 years
Proprietary technology | 2023 Acquisitions [Member] | Minimum
Acquisitions
Useful lives		6 years
Proprietary technology | 2023 Acquisitions [Member] | Maximum
Acquisitions
Useful lives		12 years
Backlog | 2023 Acquisitions [Member]
Acquisitions
Useful lives		3 months
Amortization expense				$ 5.4
Bargain Purchase [Member] | 2023 Acquisitions [Member]
Acquisitions
Number of acquisitions | agreement			1
Harsh Environment Solutions
Acquisitions
Goodwill		$ 2,001.3			$ 2,009.3
Harsh Environment Solutions | 2023 Acquisitions [Member]
Acquisitions
Number of acquisitions | agreement					5
Interconnect and Sensor Systems
Acquisitions
Goodwill		2,126.7			$ 2,105.6
Interconnect and Sensor Systems | 2023 Acquisitions [Member]
Acquisitions
Number of acquisitions | agreement					3
Communications Solutions
Acquisitions
Goodwill		$ 2,972.5			$ 2,977.5
Communications Solutions | 2023 Acquisitions [Member]
Acquisitions
Number of acquisitions | agreement					2

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets, Goodwill (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)
Goodwill.
Goodwill, Beginning Balance	$ 7,092.4
Acquisition-related	49.4
Foreign currency translation	(41.3)
Goodwill, Ending Balance	7,100.5
Harsh Environment Solutions
Goodwill.
Goodwill, Beginning Balance	2,009.3
Acquisition-related	1.2
Foreign currency translation	(9.2)
Goodwill, Ending Balance	2,001.3
Communications Solutions
Goodwill.
Goodwill, Beginning Balance	2,977.5
Acquisition-related	4.5
Foreign currency translation	(9.5)
Goodwill, Ending Balance	2,972.5
Interconnect and Sensor Systems
Goodwill.
Goodwill, Beginning Balance	2,105.6
Acquisition-related	43.7
Foreign currency translation	(22.6)
Goodwill, Ending Balance	$ 2,126.7

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets, Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Intangible Assets
Weighted average useful lives of acquired amortizable intangible assets	10 years
Gross Carrying Amount (definite-lived)	$ 1,230.4	$ 1,261.8
Accumulated Amortization	714.1	696.1
Net Carrying Amount, (definite-lived)	516.3	565.7
Indefinite-lived trade name intangible asset	269.1	269.1
Intangible assets, gross (excluding goodwill)	1,499.5	1,530.9
Net Carrying Amount, intangible assets	$ 785.4	834.8
Customer relationships
Intangible Assets
Weighted average useful lives of acquired amortizable intangible assets	10 years
Gross Carrying Amount (definite-lived)	$ 780.2	782.6
Accumulated Amortization	462.5	450.6
Net Carrying Amount, (definite-lived)	$ 317.7	332
Proprietary technology
Intangible Assets
Weighted average useful lives of acquired amortizable intangible assets	13 years
Gross Carrying Amount (definite-lived)	$ 350.8	365.1
Accumulated Amortization	152.2	146.1
Net Carrying Amount, (definite-lived)	$ 198.6	219
Backlog and other
Intangible Assets
Weighted average useful lives of acquired amortizable intangible assets	1 year
Gross Carrying Amount (definite-lived)	$ 99.4	114.1
Accumulated Amortization	99.4	99.4
Net Carrying Amount, (definite-lived)	$ 0	$ 14.7

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets, Amortization (Details) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2023 agreement
Intangible assets
Amortization expense	$ 20.4	$ 23.2
Amortization expense estimated for each of the next five fiscal years
Remainder of 2024	57.6
2025	68.2
2026	66.6
2027	59.9
2028	52.5
2029	$ 41.9
2023 Acquisitions [Member]
Intangible assets
Number of acquisitions | agreement			10
2023 Acquisitions [Member] | Backlog
Intangible assets
Amortization expense		$ 5.4

Reportable Business Segments, N

Reportable Business Segments, Net sales by segment (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($) entity segment	Mar. 31, 2023 USD ($)
Segment reporting information
Number of reportable business segments | segment	3
Number of segment managers | entity	3
Net sales	$ 3,256.3	$ 2,974
Harsh Environment Solutions
Segment reporting information
Net sales	916	854.2
Communications Solutions
Segment reporting information
Net sales	1,265.7	1,126.7
Interconnect and Sensor Systems
Segment reporting information
Net sales	1,074.6	993.1
Operating Segment | Harsh Environment Solutions
Segment reporting information
Net sales	916	854.2
Operating Segment | Communications Solutions
Segment reporting information
Net sales	1,265.7	1,126.7
Operating Segment | Interconnect and Sensor Systems
Segment reporting information
Net sales	1,074.6	993.1
Inter-Segment
Segment reporting information
Net sales	35.9	42.8
Inter-Segment | Harsh Environment Solutions
Segment reporting information
Net sales	19.6	23.8
Inter-Segment | Communications Solutions
Segment reporting information
Net sales	11.2	13.9
Inter-Segment | Interconnect and Sensor Systems
Segment reporting information
Net sales	$ 5.1	$ 5.1

Reportable Business Segments, R

Reportable Business Segments, Reconciliation of Segment Operating Income to Consolidated Income Before Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information
Operating income	$ 684.8	$ 591.7
Stock-based compensation expense	(23.8)	(21.7)
Acquisition-related expenses	0	(5.4)
Other operating expenses	(17.4)	(16.9)
Interest expense	(38.1)	(35.9)
Other income (expense), net	16	4.1
Income before income taxes	662.7	559.9
Operating Segment
Segment Reporting Information
Operating income	726	635.7
Operating Segment | Harsh Environment Solutions
Segment Reporting Information
Operating income	244.4	226.3
Operating Segment | Communications Solutions
Segment Reporting Information
Operating income	286.2	230.6
Operating Segment | Interconnect and Sensor Systems
Segment Reporting Information
Operating income	$ 195.4	$ 178.8

Reportable Business Segments, D

Reportable Business Segments, Depreciation & Amortization by Segment (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment reporting information
Depreciation and amortization	$ 103.8	$ 96.3
Harsh Environment Solutions
Segment reporting information
Depreciation and amortization	22.7	24.5
Communications Solutions
Segment reporting information
Depreciation and amortization	45.1	39.2
Interconnect and Sensor Systems
Segment reporting information
Depreciation and amortization	33.9	31
Corporate and Other
Segment reporting information
Depreciation and amortization	$ 2.1	$ 1.6

Revenue Recognition (Details)

Revenue Recognition (Details) - item	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenue recognition
Remaining performance obligation, expected timing for substantial portion of performance obligations	3 months
Practical expedient, performance obligation	true
Minimum
Revenue recognition
Number of reporting periods that may be extended across for multiple delivery dates	1
Maximum
Revenue recognition
Percentage of net sales recognized over time	5%	5%
Remaining performance obligation, expected timing for nearly all performance obligations	1 year
Practical expedient, performance obligation	true

Revenue Recognition, Disaggrega

Revenue Recognition, Disaggregation of Net Sales (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenue recognition
Net sales	$ 3,256.3	$ 2,974
United States
Revenue recognition
Net sales	1,113.1	1,052.3
China
Revenue recognition
Net sales	670.4	619.1
Other foreign locations
Revenue recognition
Net sales	1,472.8	1,302.6
End customers and contract manufacturers
Revenue recognition
Net sales	2,698.2	2,465.1
Distributors and resellers
Revenue recognition
Net sales	558.1	508.9
Harsh Environment Solutions
Revenue recognition
Net sales	916	854.2
Harsh Environment Solutions | United States
Revenue recognition
Net sales	455.1	418.8
Harsh Environment Solutions | China
Revenue recognition
Net sales	81	86.3
Harsh Environment Solutions | Other foreign locations
Revenue recognition
Net sales	379.9	349.1
Harsh Environment Solutions | End customers and contract manufacturers
Revenue recognition
Net sales	675.3	623.8
Harsh Environment Solutions | Distributors and resellers
Revenue recognition
Net sales	240.7	230.4
Communications Solutions
Revenue recognition
Net sales	1,265.7	1,126.7
Communications Solutions | United States
Revenue recognition
Net sales	346.6	336.2
Communications Solutions | China
Revenue recognition
Net sales	374.2	350
Communications Solutions | Other foreign locations
Revenue recognition
Net sales	544.9	440.5
Communications Solutions | End customers and contract manufacturers
Revenue recognition
Net sales	990.9	890.8
Communications Solutions | Distributors and resellers
Revenue recognition
Net sales	274.8	235.9
Interconnect and Sensor Systems
Revenue recognition
Net sales	1,074.6	993.1
Interconnect and Sensor Systems | United States
Revenue recognition
Net sales	311.4	297.3
Interconnect and Sensor Systems | China
Revenue recognition
Net sales	215.2	182.8
Interconnect and Sensor Systems | Other foreign locations
Revenue recognition
Net sales	548	513
Interconnect and Sensor Systems | End customers and contract manufacturers
Revenue recognition
Net sales	1,032	950.5
Interconnect and Sensor Systems | Distributors and resellers
Revenue recognition
Net sales	$ 42.6	$ 42.6