Merck & Co. (MRK) 10-Q 6 Nov 24 2024 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 30, 2024	Oct. 31, 2024
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2024
Document Transition Report	false
Entity File Number	1-6571
Entity Registrant Name	Merck & Co., Inc.
Entity Incorporation, State or Country Code	NJ
Entity Tax Identification Number	22-1918501
Entity Address, Address Line One	126 East Lincoln Avenue
Entity Address, City or Town	Rahway
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	07065
City Area Code	(908)
Local Phone Number	740-4000
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		2,529,635,645
Amendment Flag	false
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q3
Entity Central Index Key	0000310158
Current Fiscal Year End Date	--12-31
Common Stock ($0.50 par value)
Entity Information [Line Items]
Title of 12(b) Security	Common Stock ($0.50 par value)
Trading Symbol	MRK
Security Exchange Name	NYSE
1.875% Notes due 2026
Entity Information [Line Items]
Title of 12(b) Security	1.875% Notes due 2026
Trading Symbol	MRK/26
Security Exchange Name	NYSE
3.250% Notes due 2032
Entity Information [Line Items]
Title of 12(b) Security	3.250% Notes due 2032
Trading Symbol	MRK/32
Security Exchange Name	NYSE
2.500% Notes due 2034
Entity Information [Line Items]
Title of 12(b) Security	2.500% Notes due 2034
Trading Symbol	MRK/34
Security Exchange Name	NYSE
1.375% Notes due 2036
Entity Information [Line Items]
Title of 12(b) Security	1.375% Notes due 2036
Trading Symbol	MRK 36A
Security Exchange Name	NYSE
3.500% Notes due 2037
Entity Information [Line Items]
Title of 12(b) Security	3.500% Notes due 2037
Trading Symbol	MRK/37
Security Exchange Name	NYSE
3.700% Notes due 2044
Entity Information [Line Items]
Title of 12(b) Security	3.700% Notes due 2044
Trading Symbol	MRK/44
Security Exchange Name	NYSE
3.750% Notes due 2054
Entity Information [Line Items]
Title of 12(b) Security	3.750% Notes due 2054
Trading Symbol	MRK/54
Security Exchange Name	NYSE

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENT OF INCOME - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Income Statement [Abstract]
Sales	$ 16,657	$ 15,962	$ 48,544	$ 45,485
Costs, Expenses and Other
Cost of sales	4,080	4,264	11,365	12,214
Selling, general and administrative	2,731	2,519	7,952	7,700
Research and development	5,862	3,307	13,354	20,904
Restructuring costs	56	126	258	344
Other (income) expense, net	(162)	126	(151)	388
Total Costs, Expenses and Other	12,567	10,342	32,778	41,550
Income Before Taxes	4,090	5,620	15,766	3,935
Taxes on Income	929	870	2,377	2,332
Net Income	3,161	4,750	13,389	1,603
Less: Net Income Attributable to Noncontrolling Interests	4	5	15	12
Net Income Attributable to Merck & Co., Inc.	$ 3,157	$ 4,745	$ 13,374	$ 1,591
Basic Earnings per Common Share Attributable to Merck & Co., Inc. Common Shareholders (in dollars per share)	$ 1.25	$ 1.87	$ 5.28	$ 0.63
Earnings per Common Share Assuming Dilution Attributable to Merck & Co., Inc. Common Shareholders (in dollars per share)	$ 1.24	$ 1.86	$ 5.26	$ 0.62

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Statement of Comprehensive Income [Abstract]
Net Income Attributable to Merck & Co., Inc.	$ 3,157	$ 4,745	$ 13,374	$ 1,591
Other Comprehensive Loss Net of Taxes:
Net unrealized (loss) gain on derivatives, net of reclassifications	(296)	159	(99)	171
Benefit plan net (loss) gain and prior service (cost) credit, net of amortization	(13)	0	(28)	(75)
Cumulative translation adjustment	299	(175)	(83)	(244)
Other comprehensive income (loss), net of taxes	(10)	(16)	(210)	(148)
Comprehensive Income Attributable to Merck & Co., Inc.	$ 3,147	$ 4,729	$ 13,164	$ 1,443

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEET - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Current Assets
Cash and cash equivalents	$ 14,593	$ 6,841
Short-term investments	0	252
Accounts receivable (net of allowance for doubtful accounts of $79 in 2024 and $88 in 2023)	11,381	10,349
Inventories (excludes inventories of $3,995 in 2024 and $3,348 in 2023 classified in Other assets - see Note 6)	6,244	6,358
Other current assets	8,143	8,368
Total current assets	40,361	32,168
Investments	575	252
Property, Plant and Equipment, at cost, net of accumulated depreciation of $19,072 in 2024 and $18,266 in 2023	23,446	23,051
Goodwill	21,697	21,197
Other Intangibles, Net	17,010	18,011
Other Assets	14,443	11,996
Total Assets	117,532	106,675
Current Liabilities
Loans payable and current portion of long-term debt	3,149	1,372
Trade accounts payable	3,586	3,922
Accrued and other current liabilities	16,539	15,766
Income taxes payable	4,330	2,649
Dividends payable	1,982	1,985
Total current liabilities	29,586	25,694
Long-Term Debt	34,982	33,683
Deferred Income Taxes	864	871
Other Noncurrent Liabilities	7,540	8,792
Merck & Co., Inc. Stockholders’ Equity
Common stock, $0.50 par value Authorized - 6,500,000,000 shares Issued - 3,577,103,522 shares in 2024 and 2023	1,788	1,788
Other paid-in capital	44,530	44,509
Retained earnings	61,384	53,895
Accumulated other comprehensive loss	(5,371)	(5,161)
Stockholders' equity before deduction for treasury stock	102,331	95,031
Less treasury stock, at cost: 1,045,073,377 shares in 2024 and 1,045,470,249 shares in 2023	57,829	57,450
Total Merck & Co., Inc. stockholders’ equity	44,502	37,581
Noncontrolling Interests	58	54
Total equity	44,560	37,635
Liabilities and Equity	$ 117,532	$ 106,675

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEET (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 79	$ 88
Inventories classified in Other assets	3,995	3,348
Accumulated depreciation	$ 19,072	$ 18,266
Common stock, par value (in dollars per share)	$ 0.50	$ 0.50
Common stock, authorized (shares)	6,500,000,000	6,500,000,000
Common stock, issued (in shares)	3,577,103,522	3,577,103,522
Treasury stock (in shares)	1,045,073,377	1,045,470,249

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENT OF CASH FLOWS - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Cash Flows from Operating Activities
Net income	$ 13,389	$ 1,603
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization	1,720	1,582
Depreciation	1,582	1,326
Income from investments in equity securities, net	(169)	(240)
Charge for the acquisition of Eyebiotech Limited	1,350	0
Charge for the acquisition of MK-1045 (formerly CN201) from Curon Pharmaceutical	750	0
Charge for the acquisition of Harpoon Therapeutics, Inc.	656	0
Charge for the acquisition of Prometheus Biosciences, Inc.	0	10,217
Charge for the acquisition of Imago BioSciences, Inc.	0	1,192
Deferred income taxes	(633)	(968)
Share-based compensation	574	478
Other	611	(81)
Net changes in assets and liabilities	(1,812)	(2,349)
Net Cash Provided by Operating Activities	18,018	12,760
Cash Flows from Investing Activities
Capital expenditures	(2,435)	(2,874)
Purchases of securities and other investments	(64)	(704)
Proceeds from sales of securities and other investments	370	1,489
Acquisition of Eyebiotech Limited, net of cash acquired	(1,344)	0
Acquisition of Elanco Animal Health Incorporated aqua business	(1,301)	0
Acquisition of Harpoon Therapeutics, Inc., net of cash acquired	(746)	0
Acquisition of MK-1045 (formerly CN201) from Curon Pharmaceutical	(700)	0
Acquisition of Prometheus Biosciences, Inc., net of cash acquired	0	(10,705)
Acquisition of Imago BioSciences, Inc., net of cash acquired	0	(1,327)
Other	(70)	(15)
Net Cash Used in Investing Activities	(6,290)	(14,136)
Cash Flows from Financing Activities
Proceeds from issuance of debt	3,599	5,939
Payments on debt	(751)	(1,752)
Dividends paid to stockholders	(5,889)	(5,593)
Purchases of treasury stock	(817)	(953)
Proceeds from exercise of stock options	165	119
Other	(330)	(325)
Net Cash Used in Financing Activities	(4,023)	(2,565)
Effect of Exchange Rate Changes on Cash, Cash Equivalents and Restricted Cash	74	(163)
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	7,779	(4,104)
Cash, Cash Equivalents and Restricted Cash at Beginning of Year (includes restricted cash of $68 and $79 at January 1, 2024 and 2023, respectively, included in Other current assets)	6,909	12,773
Cash, Cash Equivalents and Restricted Cash at End of Period (includes restricted cash of $95 and $64 at September 30, 2024 and 2023, respectively, included in Other current assets)	$ 14,688	$ 8,669

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENT OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022
Statement of Cash Flows [Abstract]
Restricted cash	$ 95	$ 68	$ 64	$ 79

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements of Merck & Co., Inc. (Merck or the Company) have been prepared pursuant to the rules and regulations for reporting on Form 10-Q. Accordingly, certain information and disclosures required by accounting principles generally accepted in the United States (U.S.) for complete consolidated financial statements are not included herein. These interim statements should be read in conjunction with the audited financial statements and notes thereto included in Merck’s Form 10-K filed on February 26, 2024. The results of operations of any interim period are not necessarily indicative of the results of operations for the full year. In the Company’s opinion, all adjustments necessary for a fair statement of these interim statements have been included and are of a normal and recurring nature. Certain reclassifications have been made to prior year amounts to conform to the current year presentation. Recently Adopted Accounting Standard In August 2023, the Financial Accounting Standards Board (FASB) issued amended guidance that requires a newly formed joint venture to recognize and initially measure its assets and liabilities at fair value upon formation. The amended guidance includes exceptions to fair value measurement that are consistent with the accounting for business combinations guidance. The amended guidance is effective prospectively for all joint ventures with a formation date on or after January 1, 2025, however existing joint ventures have the option to apply the guidance retrospectively. The Company adopted the guidance effective July 1, 2024 on a prospective basis. There was no impact to the Company’s consolidated financial statements upon adoption. Recently Issued Accounting Standards Not Yet Adopted In November 2023, the FASB issued guidance intended to improve reportable segment disclosure requirements, primarily through expanded disclosures for significant segment expenses. The guidance is effective for annual periods beginning in 2024, and interim periods beginning in 2025. The guidance will result in incremental disclosures within the footnotes to the Company’s financial statements.

Acquisitions, Divestitures, Res

Acquisitions, Divestitures, Research Collaborations and Licensing Agreements	9 Months Ended
	Sep. 30, 2024
Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]
Acquisitions, Divestitures, Research Collaborations and Licensing Agreements	Acquisitions, Divestitures, Research Collaborations and Licensing Agreements The Company continues to pursue acquisitions and the establishment of external alliances such as research collaborations and licensing agreements to complement its internal research capabilities. These arrangements often include upfront payments; expense reimbursements or payments to the third party; milestone, royalty or profit share arrangements contingent upon the occurrence of certain future events linked to the success of the asset in development; and can also include option and continuation payments. The Company also reviews its marketed products and pipeline to examine candidates which may provide more value through out-licensing and, as part of its portfolio assessment process, may also divest certain assets. Pro forma financial information for acquired businesses is not presented if the historical financial results of the acquired entity are not significant when compared with the Company’s financial results. 2024 Transactions In September 2024, Merck acquired MK-1045 (formally CN201), a novel investigational clinical-stage bispecific antibody for the treatment of B-cell associated diseases, from Curon Biopharmaceutical (Curon) for an upfront payment of $700 million. In addition, Curon is eligible to receive future contingent developmental milestone payments of up to $300 million and regulatory milestone payments of up to $300 million. MK-1045 is currently being evaluated in Phase 1 and Phase 1b/2 clinical trials for the treatment of patients with relapsed or refractory non-Hodgkin lymphoma and relapsed or refractory B-cell acute lymphocytic leukemia, respectively. Merck plans to evaluate MK-1045 as a treatment for B-cell malignancies as well as investigate its potential to provide a novel, scalable option for the treatment of autoimmune diseases. The transaction was accounted for as an asset acquisition. Merck recorded a charge of $750 million (reflecting the upfront payment and other related costs) to Research and development expenses in the third quarter and first nine months of 2024. In connection with the agreement, Merck is also obligated to pay a third party future contingent developmental, regulatory and sales-based milestone payments of up to $128 million in the aggregate, as well as tiered royalties ranging from a mid-single-digit rate to a low-double-digit rate on future net sales of MK-1045 if approved. In July 2024, Merck acquired the aqua business of Elanco Animal Health Incorporated (Elanco aqua business) for total consideration of $1.3 billion. The Elanco aqua business consists of an innovative portfolio of medicines and vaccines, nutritionals and supplements for aquatic species; two related aqua manufacturing facilities in Canada and Vietnam; as well as a research facility in Chile. The acquisition broadens Animal Health’s aqua portfolio with products such as Clynav , a new generation DNA-based vaccine that protects Atlantic salmon against pancreas disease, and Imvixa , an anti-parasitic sea lice treatment. This acquisition also brings a portfolio of water treatment products for warm water production, complementing Animal Health’s warm water vaccine portfolio. In addition to these products, the DNA-based vaccine technology that is a part of the business has the potential to accelerate the development of novel vaccines to address the unmet needs of the aqua industry. There are no contingent payments associated with the acquisition, which was accounted for as a business combination. The estimated fair values of assets acquired and liabilities assumed from the Elanco aqua business (which are considered preliminary subject to the finalization of the tax treatment of the transaction) are as follows: ($ in millions) July 9, 2024 Inventories $ 74 Property, plant and equipment 67 Product rights - Clynav (useful life 15 years) (1) 340 Other product rights (useful lives 15 years) (1) 291 Other assets and liabilities, net 24 Total identifiable net assets 796 Goodwill (2) 505 Consideration transferred $ 1,301 (1) The estimated fair values of Clynav and other product rights were determined using an income approach, specifically the multi-period excess earnings method. The future probability-weighted net cash flows were discounted to present value utilizing a discount rate of 8.5%. Actual cash flows are likely to be different than those assumed. (2) The goodwill recognized is largely attributable to anticipated synergies expected to arise after the acquisition and was allocated to the Animal Health segment. Also in July 2024, Merck acquired Eyebiotech Limited (EyeBio), a privately held ophthalmology-focused biotechnology company for $1.2 billion (including payments to settle share-based equity awards) and also incurred $207 million of transaction costs. The acquisition agreement also provides for former EyeBio shareholders to receive future contingent developmental milestone payments of up to $200 million (of which $100 million was triggered in the third quarter of 2024 as noted below), regulatory milestone payments of up to $1.0 billion and sales-based milestone payments of up to $500 million. EyeBio’s development work focused on candidates for the prevention and treatment of vision loss associated with retinal vascular leakage, a known risk factor for retinal diseases. EyeBio’s lead candidate, Restoret ( MK-3000, formerly EYE103), is an investigational, potentially first-in-class tetravalent, tri-specific antibody that acts as an agonist of the Wingless-related integration site signaling pathway, which is in clinical development for the treatment of diabetic macular edema and neovascular age-related macular degeneration. The transaction was accounted for as an asset acquisition since Restoret accounted for substantially all of the fair value of the gross assets acquired (excluding cash and deferred income taxes). Merck recorded net assets of $21 million, as well as a charge of $1.35 billion to Research and development expenses in the third quarter and first nine months of 2024 related to the acquisition. Additionally, a $100 million developmental milestone was triggered in the third quarter of 2024 upon initiation of a Phase 2/3 clinical trial evaluating Restoret for the treatment of diabetic macular edema, which was also recorded to Research and development expenses. Additionally in July 2024, Merck and Orion Corporation (Orion) announced the mutual exercise of an option to convert the companies’ ongoing co-development and co-commercialization agreement for opevesostat (MK-5684/ODM-208), an investigational cytochrome P450 11A1 (CYP11A1) inhibitor, and other candidates targeting CYP11A1, into an exclusive global license for Merck. With the exercise of the option, Merck assumed full responsibility for all past and future development and commercialization expenses associated with the candidates covered by the original agreement. In addition, Orion became eligible to receive developmental milestone payments of up to $30 million, regulatory milestone payments of up to $625 million and sales-based milestone payments of up to $975 million, as well as annually tiered royalties ranging from a low double-digit rate up to a rate in the low twenties on net sales for any commercialized licensed product. Orion retained responsibility for the manufacture of clinical and commercial supply for Merck. No payment was associated with the exercise of the option, which became effective in September of 2024. Also in July 2024, Merck notified Kelun-Biotech (a holding subsidiary of Sichuan Kelun Pharmaceutical Co., Ltd.) it was terminating the license and collaboration agreement entered into in July 2022 in which Merck gained exclusive worldwide rights for the development, manufacture and commercialization of an investigational antibody drug conjugate (ADC) (SKB315/MK-1200) for the treatment of solid tumors. As a result of this termination, which became effective in September 2024, all rights to SKB315 have reverted to Kelun-Biotech. In March 2024, Merck acquired Harpoon Therapeutics, Inc. (Harpoon), a clinical-stage immunotherapy company developing a novel class of T-cell engagers designed to harness the power of the body’s immune system to treat patients suffering from cancer and other diseases, for $765 million and also incurred $56 million of transaction costs. Harpoon’s lead candidate, MK-6070 (formerly HPN328), is a T-cell engager targeting delta-like ligand 3 (DLL3), an inhibitory canonical Notch ligand that is expressed at high levels in small-cell lung cancer (SCLC) and neuroendocrine tumors. MK-6070 is currently being evaluated as monotherapy in a Phase 1/2 clinical trial in certain patients with advanced cancers associated with expression of DLL3. The study is also evaluating MK-6070 in combination with atezolizumab in certain patients with SCLC. The transaction was accounted for as an asset acquisition since MK-6070 represented substantially all of the fair value of the gross assets acquired (excluding cash and deferred income taxes). Merck recorded net assets of $165 million, as well as a charge of $656 million to Research and development expenses in the first nine months of 2024 related to the transaction. There are no future contingent payments associated with the acquisition. In August 2024, Merck and Daiichi Sankyo expanded their existing global co-development and co-commercialization agreement to include MK-6070. See Note 3 for more information on Merck’s collaboration with Daiichi Sankyo. 2023 Transactions In October 2023, Merck and Daiichi Sankyo entered into a global development and commercialization agreement for three of Daiichi Sankyo’s deruxtecan (DXd) ADC candidates: patritumab deruxtecan (HER3-DXd) (MK-1022), ifinatamab deruxtecan (I-DXd) (MK-2400) and raludotatug deruxtecan (R-DXd) (MK-5909) (see Note 3). In June 2023, Merck acquired Prometheus Biosciences, Inc. (Prometheus), a clinical-stage biotechnology company pioneering a precision medicine approach for the discovery, development, and commercialization of novel therapeutic and companion diagnostic products for the treatment of immune-mediated diseases. Total consideration paid of $11.0 billion included $1.2 billion of costs to settle share-based equity awards (including $700 million to settle unvested equity awards). Prometheus’ lead candidate, tulisokibart (MK-7240, formerly PRA023), is a humanized monoclonal antibody directed to tumor necrosis factor-like ligand 1A, a target associated with both intestinal inflammation and fibrosis. Tulisokibart is being developed for the treatment of immune-mediated diseases including ulcerative colitis, Crohn’s disease, and other autoimmune conditions. A Phase 3 clinical trial evaluating tulisokibart for ulcerative colitis commenced in 2023. The transaction was accounted for as an asset acquisition since tulisokibart accounted for substantially all of the fair value of the gross assets acquired (excluding cash and deferred income taxes). Merck recorded net assets of $877 million, including cash of $368 million, investments of $296 million, deferred tax assets of $218 million and other net liabilities of $5 million, as well as a charge of $10.2 billion to Research and development expenses in the first nine months of 2023 related to the transaction. There are no future contingent payments associated with the acquisition. In February 2023, Merck and Kelun-Biotech closed a license and collaboration agreement expanding their relationship in which Merck gained exclusive rights for the research, development, manufacture and commercialization of up to seven investigational preclinical ADCs for the treatment of cancer. Kelun-Biotech retained the right to research, develop, manufacture and commercialize certain licensed and option ADCs for Chinese mainland, Hong Kong and Macau. Merck made an upfront payment of $175 million, which was recorded as a charge to Research and development expenses in the first nine months of 2023. In October 2023, Merck notified Kelun-Biotech it was terminating two of the seven candidates under the agreement. Subsequently, in April 2024, Merck notified Kelun-Biotech it was terminating one additional candidate under the agreement. In July 2024, Merck notified Kelun-Biotech that it was exercising an existing license option for one of the candidates under the agreement, granting Merck a license for the development, manufacture and commercialization worldwide excluding China. There are now three candidates licensed under the original agreement and one candidate for which the license option remains unexercised. Merck paid Kelun-Biotech $38 million in connection with the July option exercise, following which Kelun-Biotech remains eligible to receive future contingent payments aggregating up to $540 million in development-related payments, $1.5 billion in regulatory milestones, and $3.1 billion in sales-based milestones if Kelun-Biotech does not retain Chinese mainland, Hong Kong and Macau rights for the remaining option ADC and all remaining candidates achieve regulatory approval. In addition, Kelun-Biotech is eligible to receive tiered royalties ranging from a mid-single-digit rate to a low-double-digit rate on future net sales for any commercialized ADC product. Also, in connection with the agreement, Merck invested $100 million in Kelun-Biotech shares in January 2023. In January 2023, Merck acquired Imago BioSciences, Inc. (Imago), a clinical stage biopharmaceutical company developing new medicines for the treatment of myeloproliferative neoplasms and other bone marrow diseases, for $1.35 billion (including payments to settle share-based equity awards) and also incurred approximately $60 million of transaction costs. Imago’s lead candidate, bomedemstat (MK-3543, formerly IMG-7289), is an investigational orally available lysine-specific demethylase 1 inhibitor currently being evaluated in multiple clinical trials for the treatment of essential thrombocythemia, myelofibrosis, and polycythemia vera, in addition to other indications. A Phase 3 clinical trial evaluating bomedemstat for the treatment of certain patients with essential thrombocythemia is underway. The transaction was accounted for as an asset acquisition since bomedemstat represented substantially all of the fair value of the gross assets acquired (excluding cash and deferred income taxes). Merck recorded net assets of $219 million, as well as a charge of $1.2 billion to Research and development expenses in the first nine months of 2023 related to the transaction. There are no future contingent payments associated with the acquisition. Spin-Off of Organon & Co. In connection with the 2021 spin-off of Organon & Co. (Organon), Merck and Organon entered into a series of interim operating agreements pursuant to which in various jurisdictions where Merck held licenses, permits and other rights in connection with marketing, import and/or distribution of Organon products prior to the separation, Merck continued to market, import and distribute such products on behalf of Organon until such time as the relevant licenses and permits transferred to Organon, with Organon receiving all of the economic benefits and burdens of such activities. As of September 30, 2024, only one jurisdiction remains under an interim operating agreement. Additionally, Merck and Organon entered into a number of manufacturing and supply agreements (MSAs) with terms ranging from four years to ten years. The amounts included in the condensed consolidated statement of operations for the above MSAs include sales of $109 million and $100 million and related cost of sales of $108 million and $106 million for the third quarter of 2024 and 2023, respectively, and sales of $309 million and $290 million and related cost of sales of $310 million and $314 million for the first nine months of 2024 and 2023, respectively. The amounts due from Organon for all spin-off related agreements were $370 million and $632 million at September 30, 2024 and December 31, 2023, respectively, and are reflected in Other current assets . The amounts due to Organon under these agreements were $130 million and $598 million at September 30, 2024 and December 31, 2023, respectively, and are included in Accrued and other current liabilities .

Collaborative Arrangements

Collaborative Arrangements	9 Months Ended
	Sep. 30, 2024
Collaborative Arrangements [Abstract]
Collaborative Arrangements	Collaborative Arrangements Merck has entered into collaborative arrangements that provide the Company with varying rights to develop, produce and market products together with its collaborative partners. Both parties in these arrangements are active participants and exposed to significant risks and rewards dependent on the commercial success of the activities of the collaboration. Merck’s more significant collaborative arrangements are discussed below. AstraZeneca PLC In 2017, Merck and AstraZeneca PLC (AstraZeneca) entered into a global strategic oncology collaboration to co-develop and co-commercialize AstraZeneca’s Lynparza (olaparib) for multiple cancer types. Independently, Merck and AstraZeneca are developing and commercializing Lynparza in combinations with their respective PD-1 and PD-L1 medicines, Keytruda (pembrolizumab) and Imfinzi. The companies are also jointly developing and commercializing AstraZeneca’s Koselugo (selumetinib) for multiple indications. Under the terms of the agreement, AstraZeneca and Merck share the development and commercialization costs for Lynparza and Koselugo monotherapy and non-PD-L1/PD-1 combination therapy opportunities. Profits from Lynparza and Koselugo product sales generated through monotherapies or combination therapies are shared equally. AstraZeneca is the principal on Lynparza and Koselugo sales transactions. Merck records its share of Lynparza and Koselugo product sales, net of cost of sales and commercialization costs, as alliance revenue, and its share of development costs associated with the collaboration as part of Research and development expenses. Reimbursements received from AstraZeneca for research and development expenses are recognized as reductions to Research and development costs. As part of the agreement, Merck made an upfront payment to AstraZeneca and also made payments over a multi-year period for certain license options. In addition, the agreement provides for contingent payments from Merck to AstraZeneca related to the successful achievement of sales-based and regulatory milestones. In 2022, Merck determined it was probable that sales of Lynparza in the future would trigger a $600 million sales-based milestone payment from Merck to AstraZeneca. Accordingly, Merck recorded a $600 million liability (which remained accrued at September 30, 2024) and a corresponding increase to the intangible asset related to Lynparza. Potential future sales-based milestone payments of $2.1 billion have not yet been accrued as they are not deemed by the Company to be probable at this time. Lynparza received regulatory approvals triggering capitalized milestone payments from Merck to AstraZeneca of $245 million and $105 million in the first nine months of 2024 and 2023, respectively (each of which had been previously accrued for). In the second quarter of 2024, the partners agreed that no future regulatory milestone payments from Merck to AstraZeneca are likely under the agreement. The intangible asset balance related to Lynparza (which includes capitalized sales-based and regulatory milestone payments) was $1.3 billion at September 30, 2024 and is included in Other Intangibles, Net . The amount is being amortized over its estimated useful life through 2028 as supported by projected future cash flows, subject to impairment testing. Summarized financial information related to this collaboration is as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Alliance revenue - Lynparza $ 337 $ 299 $ 947 $ 884 Alliance revenue - Koselugo 39 26 114 74 Total alliance revenue $ 376 $ 325 $ 1,061 $ 958 Cost of sales (1) 82 82 245 230 Selling, general and administrative 39 44 121 143 Research and development 19 23 57 65 ($ in millions) September 30, 2024 December 31, 2023 Receivables from AstraZeneca included in Other current assets $ 375 $ 341 Payables to AstraZeneca included in Accrued and other current liabilities (2) 615 256 Payables to AstraZeneca included in Other Noncurrent Liabilities (2) — 600 (1) Represents amortization of capitalized milestone payments. (2) Includes accrued milestone payments. Eisai Co., Ltd. In 2018, Merck and Eisai Co., Ltd. (Eisai) announced a strategic collaboration for the worldwide co-development and co-commercialization of Lenvima (lenvatinib), an orally available tyrosine kinase inhibitor discovered by Eisai. Under the agreement, Merck and Eisai are developing and commercializing Lenvima jointly, both as monotherapy and in combination with Keytruda . Eisai records Lenvima product sales globally (Eisai is the principal on Lenvima sales transactions) and Merck and Eisai share applicable profits equally. Merck records its share of Lenvima product sales, net of cost of sales and commercialization costs, as alliance revenue. Expenses incurred during co-development are shared by the two companies in accordance with the collaboration agreement and reflected in Research and development expenses. Certain expenses incurred solely by Merck or Eisai are not shareable under the collaboration agreement, including costs incurred in excess of agreed upon caps and costs related to certain combination studies of Keytruda and Lenvima. Under the agreement, Merck made an upfront payment to Eisai and also made payments over a multi-year period for certain option rights. In addition, the agreement provides for contingent payments from Merck to Eisai related to the successful achievement of sales-based and regulatory milestones. In the first quarter of 2023, Merck determined it was probable that sales of Lenvima in the future would trigger a $125 million sales-based milestone payment from Merck to Eisai. Similarly, in the third quarter of 2023 an additional $125 million sales-based milestone payment to Eisai was deemed by the Company to be probable of payment. Accordingly, Merck recorded $250 million of liabilities for these payments (one of which was paid in the second quarter of 2023 and the other was paid in the second quarter of 2024) and corresponding increases to the intangible asset related to Lenvima. Merck also recognized $81 million and $154 million of cumulative amortization catch-up expense related to the recognition of these milestones in the third quarter and first nine months of 2023, respectively. Potential future sales-based milestone payments of $2.3 billion have not yet been accrued as they are not deemed by the Company to be probable at this time. There are no regulatory milestone payments remaining under the agreement. The intangible asset balance related to Lenvima (which includes capitalized sales-based and regulatory milestone payments) was $502 million at September 30, 2024 and is included in Other Intangibles, Net . The amount is being amortized over its estimated useful life through 2026 as supported by projected future cash flows, subject to impairment testing. Summarized financial information related to this collaboration is as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Alliance revenue - Lenvima $ 251 $ 260 $ 755 $ 734 Cost of sales (1) 60 137 181 320 Selling, general and administrative 40 46 120 145 Research and development 4 5 18 61 ($ in millions) September 30, 2024 December 31, 2023 Receivables from Eisai included in Other current assets $ 252 $ 226 Payables to Eisai included in Accrued and other current liabilities (2) — 125 (1) Represents amortization of capitalized milestone payments. Amounts in the third quarter and first nine months of 2023 include $81 million and $154 million, respectively, of cumulative amortization catch-up expense as noted above. (2) Represents an accrued milestone payment. Bayer AG In 2014, the Company entered into a worldwide clinical development collaboration with Bayer AG (Bayer) to market and develop soluble guanylate cyclase (sGC) modulators including Bayer’s Adempas (riociguat) and Verquvo (vericiguat). The two companies have implemented a joint development and commercialization strategy. Under the agreement, Bayer commercializes Adempas in the Americas, while Merck commercializes in the rest of the world. For Verquvo, Merck commercializes in the U.S. and Bayer commercializes in the rest of the world. Both companies share in development costs and profits on sales. Merck records sales of Adempas and Verquvo in its marketing territories, as well as alliance revenue. Alliance revenue represents Merck’s share of profits from sales of Adempas and Verquvo in Bayer’s marketing territories, which are product sales net of cost of sales and commercialization costs. Cost of sales includes Bayer’s share of profits from sales in Merck’s marketing territories. In addition, the agreement provided for contingent payments from Merck to Bayer related to the successful achievement of sales-based milestones. There are no sales-based milestone payments remaining under this collaboration. The intangible asset balances related to Adempas (which includes the acquired intangible asset balance, as well as capitalized sales-based milestone payments attributed to Adempas) and Verquvo (which reflects the portion of the final sales-based milestone payment that was attributed to Verquvo) were $431 million and $47 million, respectively, at September 30, 2024 and are included in Other Intangibles, Net . The assets are being amortized over their estimated useful lives (through 2027 for Adempas and through 2031 for Verquvo) as supported by projected future cash flows, subject to impairment testing. Summarized financial information related to this collaboration is as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Alliance revenue - Adempas/Verquvo $ 102 $ 92 $ 306 $ 259 Net sales of Adempas recorded by Merck 72 65 214 189 Net sales of Verquvo recorded by Merck 11 8 25 24 Total sales $ 185 $ 165 $ 545 $ 472 Cost of sales (1) 59 53 182 165 Selling, general and administrative 29 33 88 100 Research and development 27 26 82 76 ($ in millions) September 30, 2024 December 31, 2023 Receivables from Bayer included in Other current assets $ 166 $ 156 Payables to Bayer included in Accrued and other current liabilities 82 80 (1) Includes amortization of intangible assets, cost of products sold by Merck, as well as Bayer’s share of profits from sales in Merck’s marketing territories. Ridgeback Biotherapeutics LP In 2020, Merck and Ridgeback Biotherapeutics LP (Ridgeback), a closely held biotechnology company, entered into a collaboration agreement to develop Lagevrio (molnupiravir), an investigational orally available antiviral candidate for the treatment of patients with COVID-19. Merck gained exclusive worldwide rights to develop and commercialize Lagevrio and related molecules. Following initial authorizations in certain markets in the fourth quarter of 2021, Lagevrio has since received multiple additional authorizations. Under the terms of the agreement, Ridgeback received an upfront payment and is eligible to receive future contingent payments dependent upon the achievement of certain developmental and regulatory approval milestones. The agreement also provides for Merck to reimburse Ridgeback for a portion of certain third-party contingent milestone payments and royalties on net sales, which is part of the profit-sharing calculation. Merck is the principal on sales transactions, recognizing sales and related costs, with profit-sharing amounts recorded within Cost of sales . Profits from the collaboration are split equally between the partners. Reimbursements from Ridgeback for its share of research and development costs (deducted from Ridgeback’s share of profits) are reflected as decreases to Research and development expenses. Summarized financial information related to this collaboration is as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Net sales of Lagevrio recorded by Merck $ 383 $ 640 $ 843 $ 1,236 Cost of sales (1) 204 348 491 762 Selling, general and administrative 11 21 43 72 Research and development 5 8 7 33 ($ in millions) September 30, 2024 December 31, 2023 Payables to Ridgeback included in Accrued and other current liabilities (2) $ 176 $ 113 (1) Includes cost of products sold by Merck, Ridgeback’s share of profits, royalty expense, amortization of capitalized milestone payments and inventory reserves. (2) Includes accrued royalties. Daiichi Sankyo In October 2023, Merck and Daiichi Sankyo entered into a global development and commercialization agreement for three of Daiichi Sankyo’s DXd ADC candidates: patritumab deruxtecan (HER3-DXd) (MK-1022), ifinatamab deruxtecan (I-DXd) (MK-2400) and raludotatug deruxtecan (R-DXd) (MK-5909). All three potentially first-in-class DXd ADCs are in various stages of clinical development for the treatment of multiple solid tumors both as monotherapy and/or in combination with other treatments. The companies will jointly develop and potentially commercialize these ADC candidates worldwide, except in Japan where Daiichi Sankyo will maintain exclusive rights. Daiichi Sankyo will be solely responsible for manufacturing and supply. Under the terms of the agreement, Merck made payments to Daiichi Sankyo totaling $4.0 billion in 2023. These payments included $1.0 billion ($500 million each for patritumab deruxtecan and ifinatamab deruxtecan) which may be refundable on a pro-rated basis in the event of early termination of development with respect to either program. In addition, the agreement provided for a continuation payment of $750 million related to patritumab deruxtecan, which Merck paid in October 2024, and a continuation payment of $750 million related to raludotatug deruxtecan due from Merck in October 2025. If Merck does not make the remaining continuation payment for raludotatug deruxtecan, the rights for that program will revert to Daiichi Sankyo and the non-refundable upfront payments already paid will be retained by Daiichi Sankyo. The agreement also provides for contingent payments from Merck to Daiichi Sankyo of up to an additional $5.5 billion for each DXd ADC upon the successful achievement of certain sales-based milestones. In conjunction with this transaction, Merck recorded an aggregate pretax charge of $5.5 billion to Research and development expenses in the fourth quarter of 2023 for the $4.0 billion of upfront payments and the $1.5 billion of continuation payments. Merck and Daiichi Sankyo equally share research and development costs, except for raludotatug deruxtecan, where Merck is responsible for 75% of the first $2.0 billion of research and development expenses. Merck includes its share of development costs associated with the collaboration as part of Research and development expenses. Following regulatory approval, Daiichi Sankyo will generally record sales worldwide (Daiichi Sankyo will be the principal on sales transactions) and the companies will equally share expenses as well as profits worldwide except for Japan where Daiichi Sankyo retains exclusive rights and Merck will receive a 5% sales-based royalty. Merck will record its share of product sales, net of cost of sales and commercialization costs, as alliance revenue. In August 2024, Merck and Daiichi Sankyo expanded their agreement to include MK-6070, an investigational delta-like ligand 3 (DLL3) targeting T-cell engager, which Merck obtained through its acquisition of Harpoon (see Note 2). The companies are planning to evaluate MK-6070 in combination with ifinatamab deruxtecan in certain patients with SCLC, as well as other potential combinations. Merck received an upfront cash payment of $170 million from Daiichi Sankyo (recorded within Other (income) expense, net) and has also satisfied a contingent quid obligation from the original collaboration agreement. The companies will jointly develop and commercialize MK-6070 worldwide and share research and development and commercialization expenses. Research and development expenses related to MK-6070 in combination with ifinatamab deruxtecan will be shared in a manner consistent with the original agreement for ifinatamab deruxtecan. Merck will be solely responsible for manufacturing and supply of MK-6070. If approved, Merck will generally record sales for MK-6070 worldwide (Merck will be the principal on sales transactions) and the companies will equally share expenses as well as profits worldwide, except for Japan where Merck retains exclusive rights and Daiichi Sankyo will receive a 5% sales-based royalty. Summarized financial information related to this collaboration is as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Selling, general and administrative $ 5 $ — $ 21 $ — Research and development 94 — 227 — ($ in millions) September 30, 2024 December 31, 2023 Payables to Daiichi Sankyo included in Accrued and other current liabilities $ 811 $ 800 Payables to Daiichi Sankyo included in Other Noncurrent Liabilities 750 750 Moderna, Inc. In 2022, Merck exercised its option to jointly develop and commercialize V940 (mRNA-4157), an investigational individualized neoantigen therapy, pursuant to the terms of an existing collaboration and license agreement with Moderna, Inc. (Moderna). V940 (mRNA-4157) is currently being evaluated in combination with Keytruda in multiple Phase 3 clinical trials. Merck and Moderna share costs and will share any profits equally under this worldwide collaboration. Merck records its share of development costs associated with the collaboration as part of Research and development expenses. Any reimbursements received from Moderna for research and development expenses are recognized as reductions to Research and development costs. Merck has also capitalized certain of the shared costs, which aggregated $172 million at September 30, 2024 and will be amortized over the assets’ estimated useful lives. Summarized financial information related to this collaboration is as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Selling, general and administrative $ 5 $ 2 $ 11 $ 3 Research and development 93 66 255 153 ($ in millions) September 30, 2024 December 31, 2023 Payables to Moderna included in Accrued and other current liabilities $ 68 $ 63 Bristol-Myers Squibb Company Reblozyl (luspatercept-aamt) is a first-in-class erythroid maturation recombinant fusion protein that is being commercialized through a global collaboration with Bristol-Myers Squibb Company (BMS). Reblozyl is approved in the U.S., Europe and certain other markets for the treatment of anemia in certain rare blood disorders and is also being evaluated for additional indications for hematology therapies. BMS is the principal on sales transactions for Reblozyl; however, Merck co-promotes Reblozyl (and may co-promote any future products approved under this collaboration) in North America, which is reimbursed by BMS. Merck receives tiered royalties ranging from 20% to 24% based on sales levels. This royalty will be reduced by 50% upon the earlier of patent expiry or generic entry on an indication-by-indication basis in each market. Additionally, Merck is eligible to receive future contingent sales-based milestone payments of up to $80 million. Alliance revenue related to this collaboration, consisting of royalties (recorded within Sales ) was $100 million and $261 million in the third quarter and first nine months of 2024, respectively, compared with $52 million and $142 million in the third quarter and first nine months of 2023, respectively.

Restructuring

Restructuring	9 Months Ended
	Sep. 30, 2024
Restructuring and Related Activities [Abstract]
Restructuring	Restructuring In January 2024, the Company approved a new restructuring program (2024 Restructuring Program) intended to continue the optimization of the Company’s Human Health global manufacturing network as the future pipeline shifts to new modalities and also optimize the Animal Health global manufacturing network to improve supply reliability and increase efficiency. The actions contemplated under the 2024 Restructuring Program are expected to be substantially completed by the end of 2031, with the cumulative pretax costs to be incurred by the Company to implement the program estimated to be approximately $4.0 billion. Approximately 60% of the cumulative pretax costs will be non-cash, relating primarily to the accelerated depreciation of facilities to be closed or divested. The remainder of the costs will result in cash outlays, relating primarily to facility shut-down costs. The Company recorded total pretax costs of $279 million and $701 million in the third quarter and first nine months of 2024, respectively, related to the 2024 Restructuring Program, bringing total cumulative pretax costs incurred through September 30, 2024 to $892 million. In 2019, Merck approved a global restructuring program (2019 Restructuring Program) as part of a worldwide initiative focused on optimizing the Company’s manufacturing and supply network, as well as reducing its global real estate footprint. The Company recorded total pretax costs of $199 million and $532 million in the third quarter and first nine months of 2023, respectively, related to the 2019 Restructuring Program. The actions under the 2019 Restructuring Program were substantially complete at the end of 2023 and, as of January 1, 2024, any remaining activities are being accounted for as part of the 2024 Restructuring Program. For segment reporting, restructuring charges are unallocated expenses. The following tables summarize the charges related to the restructuring programs by type of cost: Three Months Ended September 30, 2024 Nine Months Ended September 30, 2024 ($ in millions) Accelerated Depreciation Separation Costs Other Exit Costs Total Accelerated Depreciation Separation Costs Other Total 2024 Restructuring Program Cost of sales $ 40 $ — $ 152 $ 192 $ 171 $ — $ 203 $ 374 Selling, general and administrative — — 31 31 — — 67 67 Research and development — — — — — — 2 2 Restructuring costs — 11 45 56 — 122 136 258 $ 40 $ 11 $ 228 $ 279 $ 171 $ 122 $ 408 $ 701 Three Months Ended September 30, 2023 Nine Months Ended September 30, 2023 ($ in millions) Accelerated Depreciation Separation Costs Other Exit Costs Total Accelerated Depreciation Separation Costs Other Total 2019 Restructuring Program Cost of sales $ 31 $ — $ 2 $ 33 $ 74 $ — $ 20 $ 94 Selling, general and administrative 5 — 35 40 5 — 88 93 Research and development — — — — — — 1 1 Restructuring costs — 95 31 126 — 246 98 344 $ 36 $ 95 $ 68 $ 199 $ 79 $ 246 $ 207 $ 532 Accelerated depreciation costs primarily relate to manufacturing, research and administrative facilities and equipment to be sold or closed as part of the programs. Accelerated depreciation costs represent the difference between the depreciation expense to be recognized over the revised useful life of the asset, based upon the anticipated date the site will be closed or divested or the equipment disposed of, and depreciation expense as determined utilizing the useful life prior to the restructuring actions. All the sites will continue to operate up through the respective closure dates and, since future undiscounted cash flows are sufficient to recover the respective book values, Merck is recording accelerated depreciation over the revised useful life of the site assets. Anticipated site closure dates, particularly related to manufacturing locations, have been and may continue to be adjusted to reflect changes resulting from regulatory or other factors. Separation costs are associated with actual headcount reductions, as well as involuntary headcount reductions which were probable and could be reasonably estimated. Other exit costs in 2024 and 2023 include asset impairment, facility shut-down and other related costs, as well as pretax gains and losses resulting from the sales of facilities and related assets. Additionally, other activity includes certain employee-related costs associated with pension and other postretirement benefit plans (see Note 10) and share-based compensation. The following table summarizes the charges and spending relating to restructuring program activities for the nine months ended September 30, 2024: ($ in millions) Accelerated Depreciation Separation Costs Other Exit Costs Total Restructuring reserves January 1, 2024 $ — $ 681 $ 31 $ 712 Expenses 171 122 408 701 (Payments) receipts, net — (177) (122) (299) Non-cash activity (171) — (292) (463) Restructuring reserves September 30, 2024 $ — $ 626 $ 25 $ 651

Financial Instruments

Financial Instruments	9 Months Ended
	Sep. 30, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Financial Instruments	Financial Instruments Derivative Instruments and Hedging Activities The Company manages the impact of foreign exchange rate movements and interest rate movements on its earnings, cash flows and fair values of assets and liabilities through operational means and through the use of various financial instruments, including derivative instruments. A significant portion of the Company’s revenues and earnings in foreign affiliates is exposed to changes in foreign exchange rates. The objectives of and accounting related to the Company’s foreign currency risk management program, as well as its interest rate risk management activities are discussed below. Foreign Currency Risk Management The Company has established revenue hedging, balance sheet risk management and net investment hedging programs to protect against volatility of future foreign currency cash flows and changes in fair value caused by changes in foreign exchange rates. The objective of the revenue hedging program is to reduce the variability caused by changes in foreign exchange rates that would affect the U.S. dollar value of future cash flows derived from foreign currency denominated sales, primarily the euro, Japanese yen and Chinese renminbi. To achieve this objective, the Company will hedge a portion of its forecasted foreign currency denominated third-party and intercompany distributor entity sales (forecasted sales) that are expected to occur over its planning cycle, typically no more than two years into the future. The Company will layer in hedges over time, increasing the portion of forecasted sales hedged as it gets closer to the expected date of the forecasted sales. The portion of forecasted sales hedged is based on assessments of cost-benefit profiles that consider natural offsetting exposures, revenue and foreign exchange rate volatilities and correlations, and the cost of hedging instruments. The Company manages its anticipated transaction exposure principally with purchased local currency put options, forward contracts, and purchased collar options. The fair values of these derivative contracts are recorded as either assets (gain positions) or liabilities (loss positions) in the Condensed Consolidated Balance Sheet. Changes in the fair value of derivative contracts are recorded each period in either current earnings or Other comprehensive income ( OCI ), depending on whether the derivative is designated as part of a hedge transaction and, if so, the type of hedge transaction. For derivatives that are designated as cash flow hedges, the unrealized gains or losses on these contracts are recorded in Accumulated Other Comprehensive Loss ( AOCL) and reclassified into Sales when the hedged anticipated revenue is recognized. For those derivatives which are not designated as cash flow hedges, but serve as economic hedges of forecasted sales, unrealized gains or losses are recorded in Sales each period. The cash flows from both designated and non-designated contracts are reported as operating activities in the Condensed Consolidated Statement of Cash Flows. The Company does not enter into derivatives for trading or speculative purposes. The Company manages operating activities and net asset positions at each local subsidiary in order to mitigate the effects of foreign exchange on monetary assets and liabilities. Monetary assets and liabilities denominated in a currency other than the functional currency of a given subsidiary are remeasured at spot rates in effect on the balance sheet date with the effects of changes in spot rates reported in Other (income) expense, net . The Company also uses a balance sheet risk management program to mitigate the exposure of such assets and liabilities from the effects of volatility in foreign exchange. Merck principally utilizes forward exchange contracts to offset the effects of foreign exchange on exposures when it is deemed economical to do so based on a cost-benefit analysis that considers the magnitude of the exposure, the volatility of the foreign exchange rate and the cost of the hedging instrument (primarily the euro, Swiss franc, Japanese yen, and Chinese renminbi). The forward contracts are not designated as hedges and are marked to market through Other (income) expense, net . Accordingly, fair value changes in the forward contracts help mitigate the changes in the value of the remeasured assets and liabilities attributable to changes in foreign currency exchange rates, except to the extent of the spot-forward differences. These differences are not significant due to the short-term nature of the contracts, which typically have average maturities at inception of less than six months. The cash flows from these contracts are reported as operating activities in the Condensed Consolidated Statement of Cash Flows. The Company also uses forward exchange contracts to hedge a portion of its net investment in foreign operations against movements in foreign exchange rates. The forward contracts are designated as hedges of the net investment in a foreign operation. The unrealized gains or losses on these contracts are recorded in foreign currency translation adjustment within OCI and remain in AOCL until either the sale or complete or substantially complete liquidation of the subsidiary. The Company excludes certain portions of the change in fair value of its derivative instruments from the assessment of hedge effectiveness (excluded components). Changes in fair value of the excluded components are recognized in OCI . The Company recognizes in earnings the initial value of the excluded components on a straight-line basis over the life of the derivative instrument, rather than using the mark-to-market approach. The cash flows from these contracts are reported as investing activities in the Condensed Consolidated Statement of Cash Flows. Foreign exchange risk is also managed through the use of foreign currency debt. A portion of the Company’s senior unsecured euro-denominated notes have been designated as, and are effective as, economic hedges of the net investment in a foreign operation. Accordingly, foreign currency transaction gains or losses due to spot rate fluctuations on the euro-denominated debt instruments are included in foreign currency translation adjustment within OCI . The effects of the Company’s net investment hedges on OCI and the Condensed Consolidated Statement of Income are shown below: Amount of Pretax (Gain) Loss Recognized in Other Comprehensive Income (1) Amount of Pretax (Gain) Loss Recognized in Other (income) expense, net for Amounts Excluded from Effectiveness Testing Three Months Ended September 30, Nine Months Ended September 30, Three Months Ended September 30, Nine Months Ended September 30, ($ in millions) 2024 2023 2024 2023 2024 2023 2024 2023 Net Investment Hedging Relationships Foreign exchange contracts $ 1 $ (1) $ 4 $ — $ — $ — $ (2) $ 1 Euro-denominated notes 169 (100) 73 (26) — — — — (1) No amounts were reclassified from AOCL into income related to the sale of a subsidiary. Interest Rate Risk Management The Company may use interest rate swap contracts on certain investing and borrowing transactions to manage its net exposure to interest rate changes and to reduce its overall cost of borrowing. The Company does not use leveraged swaps and, in general, does not leverage any of its investment activities that would put principal at risk. At September 30, 2024, the Company was a party to six pay-floating, receive-fixed interest rate swap contracts designated as fair value hedges of a portion of fixed-rate notes as detailed in the table below. September 30, 2024 ($ in millions) Par Value of Debt Number of Interest Rate Swaps Held Total Swap Notional Amount 4.50% notes due 2033 $ 1,500 6 $ 1,500 The interest rate swap contracts are designated hedges of the fair value changes in the notes attributable to changes in the benchmark Secured Overnight Financing Rate (SOFR) swap rate. The fair value changes in the notes attributable to changes in the SOFR swap rate are recorded in interest expense along with the offsetting fair value changes in the swap contracts. The cash flows from these contracts are reported as operating activities in the Condensed Consolidated Statement of Cash Flows. The table below presents the location of amounts recorded in the Condensed Consolidated Balance Sheet related to cumulative basis adjustments for fair value hedges: Carrying Amount of Hedged Liabilities Cumulative Amount of Fair Value Hedging Adjustment Increase Included in the Carrying Amount ($ in millions) September 30, 2024 December 31, 2023 September 30, 2024 December 31, 2023 Balance Sheet Caption Long-Term Debt $ 1,589 $ 1,056 $ 98 $ 56 Presented in the table below is the fair value of derivatives on a gross basis segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments: September 30, 2024 December 31, 2023 Fair Value of Derivative U.S. Dollar Fair Value of Derivative U.S. Dollar ($ in millions) Asset Liability Asset Liability Derivatives Designated as Hedging Instruments Balance Sheet Caption Interest rate swap contracts Other Assets $ 99 $ — $ 1,500 $ 57 $ — $ 1,000 Foreign exchange contracts Other current assets 30 — 4,635 106 — 6,138 Foreign exchange contracts Other Assets 28 — 2,170 26 — 1,929 Foreign exchange contracts Accrued and other current liabilities — 118 5,022 — 76 3,680 Foreign exchange contracts Other Noncurrent Liabilities — 1 54 — 1 7 157 119 13,381 189 77 12,754 Derivatives Not Designated as Hedging Instruments Balance Sheet Caption Foreign exchange contracts Other current assets 183 — 10,298 153 — 9,693 Foreign exchange contracts Accrued and other current liabilities — 179 11,635 — 162 8,104 183 179 21,933 153 162 17,797 $ 340 $ 298 $ 35,314 $ 342 $ 239 $ 30,551 As noted above, the Company records its derivatives on a gross basis in the Condensed Consolidated Balance Sheet. The Company has master netting agreements with several of its financial institution counterparties (see Concentrations of Credit Risk below). The following table provides information on the Company’s derivative positions subject to these master netting arrangements as if they were presented on a net basis, allowing for the right of offset by counterparty and cash collateral exchanged per the master agreements and related credit support annexes: September 30, 2024 December 31, 2023 ($ in millions) Asset Liability Asset Liability Gross amounts recognized in the condensed consolidated balance sheet $ 340 $ 298 $ 342 $ 239 Gross amounts subject to offset in master netting arrangements not offset in the condensed consolidated balance sheet (225) (225) (215) (215) Cash collateral received — — (3) — Net amounts $ 115 $ 73 $ 124 $ 24 The table below provides information regarding the location and amount of pretax gains and losses of derivatives designated in fair value or cash flow hedging relationships: Three Months Ended September 30, Nine Months Ended September 30, ($ in millions) 2024 2023 2024 2023 2024 2023 2024 2023 2024 2023 2024 2023 Financial Statement Caption in which Effects of Fair Value or Cash Flow Sales Other (income) expense, net (1) Other comprehensive income (loss) Sales Other (income) expense, net (1) Other comprehensive income (loss) $ 16,657 $ 15,962 $ (162) $ 126 $ (10) $ (16) $ 48,544 $ 45,485 $ (151) $ 388 $ (210) $ (148) Loss (gain) on fair value hedging relationships: Interest rate swap contracts Hedged items — — 68 (7) — — — — 42 (7) — — Derivatives designated as hedging instruments — — (69) 8 — — — — (43) 8 — — Impact of cash flow hedging relationships: Foreign exchange contracts Amount of (loss) gain recognized in OCI on derivatives — — — — (325) 247 — — — — 22 375 Increase in Sales as a result of AOCL reclassifications 48 45 — — (48) (45) 146 170 — — (146) (170) Interest rate contracts Amount of gain recognized in Other (income) expense, net on derivatives — — — — — — — — (1) (1) — — Amount of (loss) gain recognized in OCI on derivatives — — — — — — — — — — (1) 13 (1) Interest expense is a component of Other (income) expense, net. The table below provides information regarding the income statement effects of derivatives not designated as hedging instruments: Amount of Derivative Pretax (Gain) Loss Recognized in Income Three Months Ended September 30, Nine Months Ended September 30, ($ in millions) 2024 2023 2024 2023 Derivatives Not Designated as Hedging Instruments Income Statement Caption Foreign exchange contracts (1) Other (income) expense, net $ (139) $ 60 $ (65) $ 32 Foreign exchange contracts (2) Sales 10 — (10) (3) (1) These derivative contracts primarily mitigate changes in the value of remeasured foreign currency denominated monetary assets and liabilities attributable to changes in foreign currency exchange rates. (2) These derivative contracts serve as economic hedges of forecasted transactions . At September 30, 2024, the Company estimates $161 million of pretax net unrealized losses on derivatives maturing within the next 12 months that hedge foreign currency denominated sales over that same period will be reclassified from AOCL to Sales . The amount ultimately reclassified to Sales may differ as foreign exchange rates change. Realized gains and losses are ultimately determined by actual foreign exchange rates at maturity. Investments in Debt and Equity Securities Information on investments in debt and equity securities is as follows: September 30, 2024 December 31, 2023 Amortized Gross Unrealized Fair Amortized Gross Unrealized Fair ($ in millions) Gains Losses Gains Losses U.S. government and agency securities $ 81 $ — $ — $ 81 $ 72 $ — $ — $ 72 Commercial paper — — — — 252 — — 252 Corporate notes and bonds — — — — 13 — — 13 Total debt securities $ 81 $ — $ — $ 81 $ 337 $ — $ — $ 337 Publicly traded equity securities (1) 984 764 Total debt and publicly traded equity securities $ 1,065 $ 1,101 (1) Unrealized net losses (gains) of $42 million and $(82) million were recorded in Other (income) expense, net in the third quarter and first nine months of 2024, respectively, on equity securities still held at September 30, 2024. Unrealized net gains of $61 million and $327 million were recorded in Other (income) expense, net in the third quarter and first nine months of 2023, respectively, on equity securities still held at September 30, 2023. At September 30, 2024 and September 30, 2023, the Company also had $848 million and $863 million, respectively, of equity investments without readily determinable fair values included in Other Assets . The Company records unrealized gains on these equity investments based on favorable observable price changes from transactions involving similar investments of the same investee and records unrealized losses based on unfavorable observable price changes, which are included in Other (income) expense, net . During the first nine months of 2024 , the Company recorded unrealized gains of $12 million and unrealized losses of $25 million related to certain of these equity investments still held at September 30, 2024. During the first nine months of 2023 , the Company recorded unrealized gains of $7 million and unrealized losses of $24 million related to certain of these equity investments still held at September 30, 2023. Cumulative unrealized gains and cumulative unrealized losses based on observable price changes for investments in equity investments without readily determinable fair values still held at September 30, 2024 were $302 million and $89 million, respectively. At September 30, 2024 and September 30, 2023, the Company also had $328 million and $467 million, respectively, recorded in Other Assets for equity securities held through ownership interests in investment funds. (Gains) losses recorded in Other (income) expense, net relating to these investment funds were $(21) million and $93 million for the third quarter of 2024 and 2023, respectively, and $(26) million and $66 million for the first nine months of 2024 and 2023, respectively. Fair Value Measurements Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The Company uses a fair value hierarchy which maximizes the use of observable inputs and minimizes the use of unobservable inputs when measuring fair value. There are three levels of inputs used to measure fair value with Level 1 having the highest priority and Level 3 having the lowest: Level 1 - Quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2 - Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 - Unobservable inputs that are supported by little or no market activity. Level 3 assets or liabilities are those whose values are determined using pricing models, discounted cash flow methodologies, or similar techniques with significant unobservable inputs, as well as assets or liabilities for which the determination of fair value requires significant judgment or estimation. If the inputs used to measure the financial assets and liabilities fall within more than one level described above, the categorization is based on the lowest level input that is significant to the fair value measurement of the instrument. Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis Financial assets and liabilities measured at fair value on a recurring basis are summarized below: Fair Value Measurements Using Fair Value Measurements Using Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total ($ in millions) September 30, 2024 December 31, 2023 Assets Investments Commercial paper $ — $ — $ — $ — $ — $ 252 $ — $ 252 Publicly traded equity securities 575 — — 575 252 — — 252 575 — — 575 252 252 — 504 Other assets (1) U.S. government and agency securities 81 — — 81 72 — — 72 Corporate notes and bonds — — — — 13 — — 13 Publicly traded equity securities 409 — — 409 512 — — 512 490 — — 490 597 — — 597 Derivative assets (2) Forward exchange contracts — 180 — 180 — 202 — 202 Interest rate swaps — 99 — 99 — 57 — 57 Purchased currency options — 61 — 61 — 83 — 83 — 340 — 340 — 342 — 342 Total assets $ 1,065 $ 340 $ — $ 1,405 $ 849 $ 594 $ — $ 1,443 Liabilities Other liabilities Contingent consideration $ — $ — $ 208 $ 208 $ — $ — $ 354 $ 354 Derivative liabilities (2) Forward exchange contracts — 291 — 291 — 239 — 239 Written currency options — 7 — 7 — — — — — 298 — 298 — 239 — 239 Total liabilities $ — $ 298 $ 208 $ 506 $ — $ 239 $ 354 $ 593 (1) Investments included in other assets are restricted as to use, including for the payment of benefits under employee benefit plans. (2) The fair value determination of derivatives includes the impact of the credit risk of counterparties to the derivatives and the Company’s own credit risk, the effects of which were not significant. As of September 30, 2024 and December 31, 2023, Cash and cash equivalents included $13.6 billion and $6.0 billion of cash equivalents, respectively (which would be considered Level 2 in the fair value hierarchy). Contingent Consideration Summarized information about the changes in the fair value of liabilities for contingent consideration associated with business combinations is as follows: ($ in millions) 2024 2023 Fair value January 1 $ 354 $ 456 Changes in estimated fair value (1) 2 6 Payments (148) (117) Fair value September 30 (2) $ 208 $ 345 (1) Recorded in Cost of sales, Research and development expenses, and Other (income) expense, net . Includes cumulative translation adjustments. (2) Balance at September 30, 2024, includes $163 million of current liabilities, of which $136 million relates to the termination of the Sanofi Pasteur MSD joint venture in 2016. As part of the termination, Merck recorded a liability for contingent future royalty payments of 11.5% on net sales of all Merck products that were previously sold by the joint venture through December 31, 2024. The fair value of this liability is determined utilizing the estimated amount and timing of projected cash flows using a risk-adjusted discount rate to present value the cash flows. The payments of contingent consideration during the first nine months of 2024 include $126 million related to the Sanofi Pasteur MSD liabilities described above and $22 million related to the first commercial sale of Lyfnua (gefapixant) in the European Union. The payments of contingent consideration during the first nine months of 2023 relate to the Sanofi Pasteur MSD liabilities described above. Other Fair Value Measurements Some of the Company’s financial instruments, such as cash and cash equivalents, receivables and payables, are reflected in the balance sheet at carrying value, which approximates fair value due to their short-term nature. The estimated fair value of loans payable and long-term debt (including current portion) at September 30, 2024, was $35.2 billion compared with a carrying value of $38.1 billion and at December 31, 2023, was $32.0 billion compared with a carrying value of $35.1 billion. Fair value was estimated using recent observable market prices and would be considered Level 2 in the fair value hierarchy. Concentrations of Credit Risk On an ongoing basis, the Company monitors concentrations of credit risk associated with corporate and government issuers of securities and financial institutions with which it conducts business. Credit exposure limits are established to limit a concentration with any single issuer or institution. Cash and investments are placed in instruments that meet high credit quality standards as specified in the Company’s investment policy guidelines. The majority of the Company’s accounts receivable arise from product sales in the U.S., Europe and China and are primarily due from drug wholesalers, distributors and retailers, hospitals and government agencies. The Company monitors the financial performance and creditworthiness of its customers so that it can properly assess and respond to changes in their credit profile. The Company also continues to monitor global economic conditions, including the volatility associated with international sovereign economies, and associated impacts on the financial markets and its business. The Company has accounts receivable factoring agreements with financial institutions in certain countries to sell accounts receivable. The Company factored $3.1 billion and $3.0 billion of accounts receivable as of September 30, 2024 and December 31, 2023, respectively, under these factoring arrangements, which reduced outstanding accounts receivable. The cash received from the financial institutions is reported within operating activities in the Condensed Consolidated Statement of Cash Flows. In certain of these factoring arrangements, for ease of administration, the Company will collect customer payments related to the factored receivables, which it then remits to the financial institutions, generally within thirty days after receipt. As of September 30, 2024 and December 31, 2023, the Company had collected $42 million and $44 million, respectively, on behalf of the financial institutions, which is reflected as restricted cash in Other current assets, and the related obligation to remit the cash is recorded in Accrued and other current liabilities . The net cash flows related to these collections are reported as financing activities in the Condensed Consolidated Statement of Cash Flows. The cost of factoring such accounts receivable was de minimis . Derivative financial instruments are executed under International Swaps and Derivatives Association master agreements. The master agreements with several of the Company’s financial institution counterparties also include credit support annexes. These annexes contain provisions that require collateral to be exchanged depending on the value of the derivative assets and liabilities, the Company’s credit rating, and the credit rating of the counterparty. Cash collateral received by the Company from various counterparties was $3 million at December 31, 2023. The obligation to return such collateral is recorded in Accrued and other current liabilities

Inventories

Inventories	9 Months Ended
	Sep. 30, 2024
Inventory Disclosure [Abstract]
Inventories	Inventories Inventories consisted of: ($ in millions) September 30, 2024 December 31, 2023 Finished goods $ 1,939 $ 1,954 Raw materials and work in process 8,780 8,037 Supplies 282 277 Total 11,001 10,268 Decrease to LIFO cost (762) (562) $ 10,239 $ 9,706 Recognized as: Inventories $ 6,244 $ 6,358 Other Assets 3,995 3,348 Amounts recognized as Other Assets are comprised almost entirely of raw materials and work in process inventories. At September 30, 2024 and December 31, 2023, these amounts included $3.7 billion and $2.6 billion, respectively, of inventories not expected to be sold within one year. In addition, these amounts included $334 million and $790 million at September 30, 2024 and December 31, 2023, respectively, of inventories produced in preparation for product launches.

Long-Term Debt

Long-Term Debt	9 Months Ended
	Sep. 30, 2024
Debt Disclosure [Abstract]
Long-Term Debt	Long-Term DebtIn May 2024, MSD Netherlands Capital B.V., a wholly-owned finance subsidiary of Merck, completed a registered public offering of €3.4 billion in aggregate principal amount of euro-dominated senior notes comprised of €850 million of 3.25% senior notes due 2032, €850 million of 3.50% senior notes due 2037, €850 million of 3.70% senior notes due 2044 and €850 million of 3.75% senior notes due 2054 (collectively, the Euronotes). The Company has fully and unconditionally guaranteed all of MSD Netherlands Capital B.V.’s obligations under the Euronotes and no other subsidiary of the Company will guarantee these obligations. MSD Netherlands Capital B.V. is a “finance subsidiary” as defined in Rule 13-01(a)(4)(vi) of Regulation S-X of the Exchange Act, with no assets or operations other than those related to the issuance, administration and repayment of the Euronotes. The financial condition, results of operations and cash flows of MSD Netherlands Capital B.V. are consolidated in the financial statements of the Company. The net cash proceeds from the offering were used for general corporate purposes.

Contingencies

Contingencies	9 Months Ended
	Sep. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Contingencies The Company is involved in various claims and legal proceedings of a nature considered normal to its business, including product liability, intellectual property, and commercial litigation, as well as certain additional matters including governmental and environmental matters. In the opinion of the Company, it is unlikely that the resolution of these matters will be material to the Company’s financial condition, results of operations or cash flows. Given the nature of the litigation discussed below and the complexities involved in these matters, the Company is unable to reasonably estimate a possible loss or range of possible loss for such matters until the Company knows, among other factors, (i) what claims, if any, will survive dispositive motion practice, (ii) the extent of the claims, including the size of any potential class, particularly when damages are not specified or are indeterminate, (iii) how the discovery process will affect the litigation, (iv) the settlement posture of the other parties to the litigation and (v) any other factors that may have a material effect on the litigation. The Company records accruals for contingencies when it is probable that a liability has been incurred and the amount can be reasonably estimated. These accruals are adjusted periodically as assessments change or additional information becomes available. Generally, for product liability claims, a portion of the overall accrual is actuarially determined and considers such factors as past experience, number of claims reported and estimates of claims incurred but not yet reported. Individually significant contingent losses are accrued when probable and reasonably estimable. Legal defense costs expected to be incurred in connection with a loss contingency are accrued when probable and reasonably estimable. The Company’s decision to obtain insurance coverage is dependent on market conditions, including cost and availability, existing at the time such decisions are made. The Company has evaluated its risks and has determined that the cost of obtaining product liability insurance outweighs the likely benefits of the coverage that is available and, as such, has no insurance for most product liabilities. Product Liability Litigation Dr. Scholl’s Foot Powder As previously disclosed, Merck is a defendant in product liability lawsuits in the U.S. arising from consumers’ alleged exposure to talc in Dr. Scholl’s foot powder, which Merck acquired through its merger with Schering-Plough Corporation and sold as part of the divestiture of Merck’s consumer care business to Bayer in 2014. In these actions, plaintiffs allege that they were exposed to asbestos-contaminated talc and developed mesothelioma as a result. As of September 30, 2024, approximately 330 cases were pending against Merck in various state courts. Gardasil/Gardasil 9 As previously disclosed, Merck is a defendant in product liability lawsuits in the U.S. involving Gardasil (Human Papillomavirus Quadrivalent [Types 6, 11, 16 and 18] Vaccine, Recombinant) and Gardasil 9 (Human Papillomavirus 9-valent Vaccine, Recombinant). As of September 30, 2024, approximately 210 cases were filed and pending against Merck in either federal or state court. In these actions, plaintiffs allege, among other things, that they suffered various personal injuries after vaccination with Gardasil or Gardasil 9, with postural orthostatic tachycardia syndrome as a predominate alleged injury. In August 2022, the U.S. Judicial Panel on Multidistrict Litigation ordered that Gardasil/Gardasil 9 product liability cases pending in federal courts nationwide be transferred to Judge Robert J. Conrad in the Western District of North Carolina for coordinated pre-trial proceedings. In February 2024, the multidistrict litigation was reassigned to Judge Kenneth D. Bell. One state court action in Los Angeles County is now scheduled to commence trial on January 21, 2025. As previously disclosed, there are fewer than 15 product liability cases pending outside the U.S. Commercial and Other Litigation Qui Tam Litigation As previously disclosed, in June 2012, the U.S. District Court for the Eastern District of Pennsylvania unsealed a complaint that had been filed against the Company under the federal False Claims Act by two former employees alleging, among other things, that the Company defrauded the U.S. government by falsifying data in connection with a clinical study conducted on the mumps component of the Company’s M-M-R II vaccine. The complaint alleges the fraud took place between 1999 and 2001. The U.S. government had the right to participate in and take over the prosecution of this lawsuit but notified the court that it declined to exercise that right. The two former employees are pursuing the lawsuit without the involvement of the U.S. government. In July 2023, the court denied relators’ motion for summary judgment, granted two of the Company’s motions for summary judgment, and denied the Company’s remaining motions for summary judgment as moot. The court entered judgment in favor of the Company and dismissed relators’ amended complaint in full with prejudice. Relators appealed that decision, and on August 6, 2024, the Third Circuit affirmed the district court’s decision. In addition, as previously disclosed, two putative class action lawsuits on behalf of direct purchasers of the M-M-R II vaccine, which charge that the Company misrepresented the efficacy of the M-M-R II vaccine in violation of federal antitrust laws and various state consumer protection laws, are pending in the Eastern District of Pennsylvania. The court granted the Company’s motion for summary judgment as to plaintiffs’ state law claims and denied the motion as to plaintiffs’ antitrust claim. The Company appealed the antitrust decision, and on October 7, 2024, the Third Circuit reversed-in-part the district court’s order and remanded the case with instructions to enter summary judgment for the Company. 340B Program Litigation As previously disclosed, Merck filed a complaint in the U.S. District Court for the District of Columbia to challenge the letter Merck received from the U.S. Health Resources and Services Administration (HRSA) in May 2022 regarding Merck’s 340B Program integrity initiative. On September 17, 2024, the court entered a consent judgment granting Merck the relief it had sought in the litigation, including declarations that HRSA’s May 2022 letter was unlawful and that the version of Merck’s 340B Program integrity initiative at issue in the litigation did not violate Section 340B on its face. Governmental Proceedings Civil Investigative Demand As previously disclosed, in June 2024, Merck received a Civil Investigative Demand (CID) from the U.S. Department of Justice, pursuant to a False Claims Act investigation, seeking documents and materials related to Steglatro , Januvia and certain related drugs. The CID states that it is investigating Merck’s price reporting under the Medicaid Drug Rebate Program as well as compliance with anti-kickback requirements in connection with patient assistance programs. The Company is cooperating with the investigation. Other Matters As previously disclosed, from time to time, the Company’s subsidiaries in China receive inquiries regarding their operations from various Chinese governmental agencies. Some of these inquiries may be related to matters involving other multinational pharmaceutical companies, as well as Chinese entities doing business with such companies. The Company’s policy is to cooperate with these authorities and to provide responses as appropriate. As previously disclosed, from time to time, the Company receives inquiries and is the subject of preliminary investigation activities from competition and other governmental authorities in markets outside the U.S. These authorities may include regulators, administrative authorities, and law enforcement and other similar officials, and these preliminary investigation activities may include site visits, formal or informal requests or demands for documents or materials, inquiries or interviews and similar matters. Certain of these preliminary inquiries or activities may lead to the commencement of formal proceedings. Should those proceedings be determined adversely to the Company, monetary fines and/or remedial undertakings may be required. Patent Litigation From time to time, generic manufacturers of pharmaceutical products file abbreviated New Drug Applications (ANDAs) with the U.S. Food and Drug Administration (FDA) seeking to market generic forms of the Company’s products prior to the expiration of relevant patents owned by the Company. To protect its patent rights, the Company may file patent infringement lawsuits against such generic companies. Similar lawsuits defending the Company’s patent rights may exist in other countries. The Company intends to vigorously defend its patents, which it believes are valid, against infringement by companies attempting to market products prior to the expiration of such patents. As with any litigation, there can be no assurance of the outcomes, which, if adverse, could result in significantly shortened periods of exclusivity for these products and, with respect to products acquired through acquisitions accounted for as business combinations, potentially significant intangible asset impairment charges. Bridion — As previously disclosed, between January and November 2020, the Company received multiple Paragraph IV Certification Letters under the Hatch-Waxman Act notifying the Company that generic drug companies had filed applications to the FDA seeking pre-patent expiry approval to sell generic versions of Bridion (sugammadex) Injection. In March, April and December 2020, the Company filed patent infringement lawsuits in the U.S. District Courts for the District of New Jersey and the Northern District of West Virginia against those generic companies. All actions in the District of New Jersey were consolidated. The West Virginia case was jointly dismissed with prejudice in August 2022 in favor of proceeding in New Jersey. The remaining defendants in the New Jersey action stipulated to infringement of the asserted claims and withdrew all remaining claims and defenses other than a defense seeking to shorten the patent term extension (PTE) of the sugammadex patent to December 2022. As previously disclosed, in June 2023, the U.S. District Court for the District of New Jersey ruled in Merck’s favor. The court held that Merck’s calculation of PTE for the sugammadex patent covering the compound is not invalid and that the U.S. Patent & Trademark Office correctly granted a full five-year extension. This ruling affirms and validates Merck’s U.S. patent protection for Bridion through at least January 2026. Also in June 2023, the U.S. District Court for the District of New Jersey issued a final judgment prohibiting the FDA from approving any of the pending or tentatively approved generic applications until January 27, 2026, except for any subsequent agreements between defendants and Merck or further order by the court. In July 2023, defendants filed a notice of appeal with the U.S. Court of Appeals for the Federal Circuit. The appeal is currently pending. While the New Jersey action was pending, the Company settled with five of these generic companies providing that these generic companies can bring their generic versions of Bridion to the market in January 2026 (which may be delayed by any applicable pediatric exclusivity) or earlier under certain circumstances. The Company agreed to stay the lawsuit filed against two other generic companies, which in exchange agreed to be bound by a judgment on the merits of the consolidated action in the District of New Jersey. One of the generic companies in the consolidated action requested dismissal of the action against it and the Company did not oppose this request, which was subsequently granted by the court. The Company does not expect this company to bring its generic version of Bridion to the market before January 2026 or later, depending on any applicable pediatric exclusivity. On February 5, 2024, the Company received another Paragraph IV Certification Letter under the Hatch-Waxman Act notifying the Company that Hikma Pharmaceuticals USA Inc. (Hikma) had filed an application to the FDA seeking pre-patent expiry approval to sell a generic version of Bridion Injection. On March 15, 2024, the Company filed a patent infringement lawsuit in the U.S. District Court for the District of New Jersey against Hikma, postponing FDA approval of the Hikma generic drug for 30 months or until expiration of the sugammadex patent (January 27, 2026) and any potentially applicable pediatric exclusivity or an adverse court decision, if any, whichever may occur earlier. Expiration of the patent, and any potentially applicable pediatric exclusivity, will occur earlier than expiry of the 30-month stay. On April 16, 2024, the district court stayed the case during the pendency of the Federal Circuit appeal noted above. Januvia, Janumet, Janumet XR — As previously disclosed, the FDA granted pediatric exclusivity with respect to Januvia (sitagliptin), Janumet (sitagliptin/metformin HCI), and Janumet XR (sitagliptin and metformin HCl extended-release), which provides a further six months of exclusivity in the U.S. beyond the expiration of all patents listed in the FDA’s Orange Book. Adding this exclusivity to the term of the key patent protection extended exclusivity on these products to January 2023. However, Januvia , Janumet , and Janumet XR contain sitagliptin phosphate monohydrate and the Company has another patent covering certain phosphate salt and polymorphic forms of sitagliptin that expires in May 2027, including pediatric exclusivity (2027 salt/polymorph patent). As previously disclosed, beginning in 2019, a number of generic drug companies filed ANDAs seeking approval of generic forms of Januvia and Janumet along with paragraph IV certifications challenging the validity of the 2027 salt/polymorph patent. The Company responded by filing infringement lawsuits which have all been settled. The Company has settled with a total of 26 generic companies providing that these generic companies can bring their generic versions of Januvia and Janumet to the market in the U.S. in May 2026 or earlier under certain circumstances, and their generic versions of Janumet XR to the market in July 2026 or earlier under certain circumstances. In March 2021, the Company filed a patent infringement lawsuit in the U.S. District Court for the District of Delaware against Zydus Worldwide DMCC, Zydus Pharmaceuticals (USA) Inc., and Cadila Healthcare Ltd. (collectively, Zydus). In that lawsuit, the Company alleged infringement of the 2027 salt/polymorph patent based on the filing of Zydus’s NDA seeking approval of a form of sitagliptin that is a different form than that used in Januvia . In December 2022, the parties reached settlement that included dismissal of the case without prejudice enabling Zydus to seek final approval of a non-automatically substitutable product. In January 2023, the Company received a Paragraph IV Certification Letter under the Hatch-Waxman Act notifying the Company that Zydus filed an ANDA seeking approval of sitagliptin/metformin HCl tablets and certifying that no valid or enforceable claim of any of the patents listed in FDA’s Orange Book for Janumet will be infringed by the proposed Zydus product. In March 2023, the parties reached settlement enabling Zydus to seek final approval of a non-automatically substitutable product containing a different form of sitagliptin than that used in Janumet. In November 2023, the Company received a Paragraph IV Certification Letter under the Hatch-Waxman Act notifying the Company that Zydus filed an ANDA seeking approval of sitagliptin/metformin HCl Extended Release tablets. In January 2024, the parties reached settlement enabling Zydus to seek final approval of a non-automatically substitutable version containing a different form of sitagliptin than that used in Janumet XR . As a result of these settlement agreements related to the later expiring 2027 salt/polymorph patent directed to the specific sitagliptin salt form of the products, the Company expects that Januvia and Janumet will not lose market exclusivity in the U.S. until May 2026 and Janumet XR will not lose market exclusivity in the U.S. until July 2026 , although Zydus has received FDA approval for a non-automatically substitutable form of sitagliptin that differs from the form in the Company’s sitagliptin products . In March 2024, the Company received another Paragraph IV Certification Letter under the Hatch-Waxman Act from Azurity Pharmaceuticals, Inc. (Azurity) asserting that a different sitagliptin product subject to its ANDA does not infringe the salt patent. On May 3, 2024, Merck filed a civil action in the U.S. District Court of Delaware alleging infringement. The case was dismissed without prejudice on July 26, 2024. Following the dismissal, the Company granted Azurity a covenant not to assert the salt patent against the Azurity product that is the subject of such ANDA. Supplementary Protection Certificates (SPCs) for Janumet expired in April 2023 for the majority of European countries. Prior to expiration, generic companies sought revocation of the Janumet SPCs in a number of European countries. In February 2022, a Finnish court referred certain questions to the Court of Justice of the European Union (CJEU) that could determine the validity of the Janumet SPCs in Europe, for which an oral hearing was held in March 2023 and an Advocate General Opinion was received on June 6, 2024, with a decision expected later in 2024. If the CJEU renders a decision that negatively impacts the validity of the Janumet SPCs throughout Europe, generic companies that were prevented from launching products during the SPC period in certain European countries may have an action for damages. Those countries include Belgium, Czech Republic, Ireland, Finland, France, Slovakia and Switzerland. If the Janumet SPCs are ultimately upheld, the Company has reserved its rights related to the pursuit of damages for those countries where a generic launched prior to expiry of the Janumet SPC. In October 2023, the Company filed a patent infringement lawsuit against Sawai Pharmaceuticals Co., Ltd. and Medisa Shinyaku Co., Ltd (collectively, Defendants) in the Tokyo District Court seeking an injunction to stop the manufacture, sale and offer for sale of the Defendants’ sitagliptin dihydrogen phosphate product, while the Company’s patents and patent term extensions are in force. The lawsuit is in response to the Defendants’ application for marketing authorization to sell a generic sitagliptin dihydrogen phosphate product, in the anhydrate form, which was approved on August 15, 2023. Merck asserts that the Defendants’ activity infringes a patent term extension associated with Merck’s patent directed to the sitagliptin compound patent. Keytruda — As previously disclosed, in November 2022, the Company filed a complaint against The Johns Hopkins University (JHU) in the U.S. District Court of Maryland. This action concerns patents emerging from a joint research collaboration between Merck and JHU regarding the use of pembrolizumab, which Merck sells under the trade name Keytruda . Merck and JHU partnered to design and conduct a clinical study administering Keytruda to cancer patients having tumors that had the genetic biomarker known as microsatellite instability-high (MSI-H). After the conclusion of the study, JHU secured U.S. patents citing the joint research study. Merck alleges that JHU has breached the collaboration agreement by filing and obtaining these patents without informing or involving Merck and then licensing the patents to others. Merck therefore brought this action for breach of contract, declaratory judgment of noninfringement, and promissory estoppel. JHU answered the complaint in April and May 2023, denying Merck’s claims, and counterclaiming for willful infringement of nine issued U.S. patents, including a demand for damages. Between November 30, 2023, and March 13, 2024, the Company filed inter partes review (IPR) petitions with the United States Patent & Trademark Office Patent Trial and Appeal Board (PTAB), challenging the validity of all nine patents asserted in the case. Between June 13, 2024 and October 3, 2024, the PTAB instituted a review of all nine asserted patents. On July 1, 2024, the district court granted Merck’s motion to stay the case in its entirety pending the outcome of the PTAB proceeding instituted on June 13, 2024. Lynparza — As previously disclosed, in December 2022, AstraZeneca Pharmaceuticals LP received a Paragraph IV Certification Letter under the Hatch-Waxman Act notifying AstraZeneca that Natco Pharma Limited (Natco) has filed an application to the FDA seeking pre-patent expiry approval to sell generic versions of Lynparza (olaparib) tablet. In February 2023, AstraZeneca and the Company filed a patent infringement lawsuit in the U.S. District Court for the District of New Jersey/Delaware against Natco. This lawsuit, which asserts one or more patents covering olaparib, automatically stays FDA approval of the generic application until June 2025 or until an adverse court decision, if any, whichever may occur earlier. In May and July 2024, AstraZeneca and the Company filed additional patent infringement lawsuits in the U.S. District Court for the District of New Jersey against Natco asserting additional patents covering olaparib. In December 2023, AstraZeneca Pharmaceuticals LP received a second Paragraph IV Certification Letter under the Hatch-Waxman Act notifying AstraZeneca that Sandoz Inc. (Sandoz) has filed an application to the FDA seeking pre-patent expiry approval to sell generic versions of Lynparza (olaparib) tablet. In February 2024, AstraZeneca and the Company filed a patent infringement lawsuit in the U.S. District Court for the District of New Jersey against Sandoz. This lawsuit, which asserts one or more patents covering olaparib, automatically stays FDA approval of the generic application until June 2026 or until an adverse court decision, if any, whichever may occur earlier. In May and July 2024, AstraZeneca and the Company filed additional patent infringement lawsuits in the U.S. District Court for the District of New Jersey against Sandoz asserting additional patents covering olaparib. In May 2024, AstraZeneca Pharmaceuticals LP received a third Paragraph IV Certification Letter under the Hatch-Waxman Act notifying AstraZeneca that Cipla USA, Inc. and Cipla Limited (collectively, Cipla) filed an application to the FDA seeking pre-patent expiry approval to sell generic versions of Lynparza (olaparib) tablet. In June 2024, AstraZeneca and the Company filed a patent infringement lawsuit in the U.S. District Court for the District of New Jersey against Cipla. This lawsuit, which asserts one or more patents covering olaparib, automatically stays FDA approval of the generic application until November 2026 or until an adverse court decision, if any, whichever may occur earlier. In June and July 2024, AstraZeneca and the Company filed additional patent infringement lawsuits in the U.S. District Court for the District of New Jersey against Cipla asserting additional patents covering olaparib. Other Litigation There are various other pending legal proceedings involving the Company, principally product liability and intellectual property lawsuits. While it is not feasible to predict the outcome of such proceedings, in the opinion of the Company, either the likelihood of loss is remote or any reasonably possible loss associated with the resolution of such proceedings is not expected to be material to the Company’s financial condition, results of operations or cash flows either individually or in the aggregate. Legal Defense Reserves Legal defense costs expected to be incurred in connection with a loss contingency are accrued when probable and reasonably estimable. Some of the significant factors considered in the review of these legal defense reserves are as follows: the actual costs incurred by the Company; the development of the Company’s legal defense strategy and structure in light of the scope of its litigation; the number of cases being brought against the Company; the costs and outcomes of completed trials; and the most current information regarding anticipated timing, progression, and related costs of pre-trial activities and trials in the associated litigation. The amount of legal defense reserves as of September 30, 2024 and December 31, 2023 of approximately $210 million represents the Company’s best estimate of the minimum amount of defense costs to be incurred in connection with its outstanding litigation; however, events such as additional trials and other events that could arise in the course of its litigation could affect the ultimate amount of legal defense costs to be incurred by the Company. The Company will continue to monitor its legal defense costs and review the adequacy of the associated reserves and may determine to increase the reserves at any time in the future if, based upon the factors set forth, it believes it would be appropriate to do so.

Equity

Equity	9 Months Ended
	Sep. 30, 2024
Equity [Abstract]
Equity	Equity Three Months Ended September 30, Common Stock Other Retained Accumulated Treasury Stock Non- Total ($ and shares in millions except per share amounts) Shares Par Value Shares Cost Balance at July 1, 2023 3,577 $ 1,788 $ 44,219 $ 54,198 $ (4,900) 1,038 $ (56,612) $ 49 $ 38,742 Net income attributable to Merck & Co., Inc. — — — 4,745 — — — — 4,745 Other comprehensive loss, net of taxes — — — — (16) — — — (16) Cash dividends declared on common stock ($0.73 per share) — — — (1,861) — — — — (1,861) Treasury stock shares purchased — — — — — 4 (466) — (466) Share-based compensation plans and other — — 139 — — — 12 — 151 Net income attributable to noncontrolling interests — — — — — — — 5 5 Balance at September 30, 2023 3,577 $ 1,788 $ 44,358 $ 57,082 $ (4,916) 1,042 $ (57,066) $ 54 $ 41,300 Balance at July 1, 2024 3,577 $ 1,788 $ 44,362 $ 60,187 $ (5,361) 1,041 $ (57,394) $ 66 $ 43,648 Net income attributable to Merck & Co., Inc. — — — 3,157 — — — — 3,157 Other comprehensive loss, net of taxes — — — — (10) — — — (10) Cash dividends declared on common stock ($0.77 per share) — — — (1,960) — — — — (1,960) Treasury stock shares purchased — — — — — 4 (444) — (444) Share-based compensation plans and other — — 168 — — — 9 — 177 Net income attributable to noncontrolling interests — — — — — — — 4 4 Distributions attributable to noncontrolling interests — — — — — — — (12) (12) Balance at September 30, 2024 3,577 $ 1,788 $ 44,530 $ 61,384 $ (5,371) 1,045 $ (57,829) $ 58 $ 44,560 Nine Months Ended September 30, Common Stock Other Retained Accumulated Treasury Stock Non- Total ($ and shares in millions except per share amounts) Shares Par Value Shares Cost Balance at January 1, 2023 3,577 $ 1,788 $ 44,379 $ 61,081 $ (4,768) 1,039 $ (56,489) $ 67 $ 46,058 Net income attributable to Merck & Co., Inc. — — — 1,591 — — — — 1,591 Other comprehensive loss, net of taxes — — — — (148) — — — (148) Cash dividends declared on common stock ($2.19 per share) — — — (5,590) — — — — (5,590) Treasury stock shares purchased — — — — — 9 (953) — (953) Share-based compensation plans and other — — (21) — — (6) 376 — 355 Net income attributable to noncontrolling interests — — — — — — — 12 12 Distributions attributable to noncontrolling interests — — — — — — — (25) (25) Balance at September 30, 2023 3,577 $ 1,788 $ 44,358 $ 57,082 $ (4,916) 1,042 $ (57,066) $ 54 $ 41,300 Balance at January 1, 2024 3,577 $ 1,788 $ 44,509 $ 53,895 $ (5,161) 1,045 $ (57,450) $ 54 $ 37,635 Net income attributable to Merck & Co., Inc. — — — 13,374 — — — — 13,374 Other comprehensive loss, net of taxes — — — — (210) — — — (210) Cash dividends declared on common stock ($2.31 per share) — — — (5,885) — — — — (5,885) Treasury stock shares purchased — — — — — 7 (817) — (817) Share-based compensation plans and other — — 21 — — (7) 438 1 460 Net income attributable to noncontrolling interests — — — — — — — 15 15 Distributions attributable to noncontrolling interests — — — — — — — (12) (12) Balance at September 30, 2024 3,577 $ 1,788 $ 44,530 $ 61,384 $ (5,371) 1,045 $ (57,829) $ 58 $ 44,560

Pension and Other Postretiremen

Pension and Other Postretirement Benefit Plans	9 Months Ended
	Sep. 30, 2024
Retirement Benefits [Abstract]
Pension and Other Postretirement Benefit Plans	Pension and Other Postretirement Benefit Plans The Company has defined benefit pension plans covering eligible employees in the U.S. and in certain of its international subsidiaries. The net periodic benefit cost (credit) of such plans consisted of the following components: Three Months Ended Nine Months Ended 2024 2023 2024 2023 ($ in millions) U.S. International U.S. International U.S. International U.S. International Service cost $ 100 $ 60 $ 88 $ 48 $ 273 $ 182 $ 239 $ 148 Interest cost 134 74 130 76 403 220 396 225 Expected return on plan assets (206) (139) (182) (131) (621) (416) (553) (390) Amortization of unrecognized prior service (credit) cost — (3) — (6) — (10) (1) 5 Net loss (gain) amortization 12 1 — (1) 30 4 — (2) Termination benefits 1 — 1 — 5 — 2 — Curtailments — — — — — — 5 — Settlements — — — — — — 26 — $ 41 $ (7) $ 37 $ (14) $ 90 $ (20) $ 114 $ (14) The Company provides medical benefits, principally to its eligible U.S. retirees and similar benefits to their dependents, through its other postretirement benefit plans. The net credit of such plans consisted of the following components: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Service cost $ 7 $ 8 $ 23 $ 24 Interest cost 14 16 42 47 Expected return on plan assets (20) (16) (60) (48) Amortization of unrecognized prior service credit (11) (12) (32) (37) Net gain amortization (14) (11) (38) (31) Curtailments — — — (1) $ (24) $ (15) $ (65) $ (46) In connection with restructuring actions (see Note 4), termination charges were recorded on pension plans related to expanded eligibility for certain employees exiting Merck. Also, in connection with these restructuring activities, curtailments were recorded on certain pension plans. In addition, lump sum payments to U.S. pension plan participants triggered partial settlement charges in the third quarter and first nine months of 2023. These partial settlements triggered remeasurements of some of the Company’s U.S. pension plans. The third quarter 2023 remeasurement, which was calculated using discount rates and asset values as of September 30, 2023, resulted in a net decrease of $34 million to net pension liabilities and a related adjustment to AOCL . Remeasurements during the first nine months of 2023 resulted in a net increase of $13 million to net pension liabilities and also resulted in a related adjustment to AOCL . The components of net periodic benefit cost (credit) other than the service cost component are included in Other (income) expense, net (see Note 11), with the exception of certain amounts for termination benefits, curtailments and settlements, which are recorded in Restructuring costs if the event giving rise to the termination benefits, curtailment or settlement related to restructuring actions.

Other (Income) Expense, Net

Other (Income) Expense, Net	9 Months Ended
	Sep. 30, 2024
Other Income and Expenses [Abstract]
Other (Income) Expense, Net	Other (Income) Expense, Net Other (income) expense, net, consisted of: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Interest income $ (127) $ (73) $ (269) $ (295) Interest expense 330 317 943 836 Exchange losses 33 85 177 208 Loss (income) from investments in equity securities, net (1) 31 33 (169) (240) Net periodic defined benefit plan (credit) cost other than service cost (157) (138) (476) (364) Other, net (272) (98) (357) 243 $ (162) $ 126 $ (151) $ 388 (1) Includes net realized and unrealized gains and losses from investments in equity securities either owned directly or through ownership interests in investment funds. Unrealized gains and losses from investments that are directly owned are determined at the end of the reporting period, while gains and losses from ownership interests in investment funds are accounted for on a one quarter lag. Other, net (as reflected in the table above) in the first nine months of 2023 includes a $572.5 million charge related to settlements with certain plaintiffs in the Zetia antitrust litigation. Interest paid for the nine months ended September 30, 2024 and 2023 was $822 million and $678 million, respectively.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2024
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The effective income tax rate of 22.7% for the third quarter of 2024 reflects a 7.2 percentage point combined unfavorable impact of charges related to the acquisitions of EyeBio and MK-1045, which had minimal tax benefits. The effective income tax rate of 15.1% for the first nine months of 2024 reflects a 2.1 percentage point combined unfavorable impact of charges related to the acquisitions of Harpoon, EyeBio and MK-1045, which had minimal tax benefits. The effective income tax rate for the first nine months of 2024 also reflects a 1.6 percentage point favorable impact due to a $259 million reduction in reserves for unrecognized income tax benefits resulting from the expiration in June 2024 of the statute of limitations for assessments related to the 2019 federal tax return year. The effective income tax rate of 15.5% for the third quarter of 2023 reflects the favorable mix of income and expense. The effective income tax rate of 59.3% for the first nine months of 2023 includes a 44.0 percentage point combined unfavorable impact of charges for the acquisitions of Prometheus and Imago for which no tax benefits were recognized, as well as higher foreign taxes, the impact of the R&D capitalization provision of the Tax Cuts and Jobs Act of 2017 (TCJA) on the Company’s U.S. global intangible low-taxed income inclusion, and net unrealized gains from investments in equity securities, which were taxed at the U.S. tax rate, partially offset by higher foreign tax credits. The Internal Revenue Service (IRS) is currently conducting examinations of the Company’s tax returns for the years 2017 and 2018, including the one-time transition tax enacted under the TCJA. If the IRS disagrees with the Company’s transition tax position, it may result in a significant tax liability. The statute of limitations for assessments with respect to the 2019 and 2020 federal tax return years expired in June 2024 (as noted above) and October 2024, respectively. Merck expects to record a benefit of approximately $270 million in the fourth quarter of 2024 due to a reduction in reserves for unrecognized tax benefits resulting from the expiration of the statute of limitations related to the 2020 federal tax return year.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2024
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The calculations of earnings per share are as follows: Three Months Ended Nine Months Ended ($ and shares in millions except per share amounts) 2024 2023 2024 2023 Net Income Attributable to Merck & Co., Inc. $ 3,157 $ 4,745 $ 13,374 $ 1,591 Average common shares outstanding 2,534 2,537 2,534 2,538 Common shares issuable (1) 7 9 9 11 Average common shares outstanding assuming dilution 2,541 2,546 2,543 2,549 Basic Earnings per Common Share Attributable to Merck & Co., Inc. Common Shareholders $ 1.25 $ 1.87 $ 5.28 $ 0.63 Earnings per Common Share Assuming Dilution Attributable to Merck & Co., Inc. Common Shareholders $ 1.24 $ 1.86 $ 5.26 $ 0.62 (1) Issuable primarily under share-based compensation plans. For the third quarter of 2024 and 2023, 7 million and 6 million, respectively, and for the first nine months of 2024 and 2023, 6 million and 5 million, respectively, of common shares issuable under share-based compensation plans were excluded from the computations of earnings per common share assuming dilution because the effect would have been antidilutive.

Other Comprehensive Income (Los

Other Comprehensive Income (Loss)	9 Months Ended
	Sep. 30, 2024
Equity [Abstract]
Other Comprehensive Income (Loss)	Other Comprehensive Income (Loss) Changes in each component of other comprehensive income (loss) are as follows: Three Months Ended September 30, ($ in millions) Derivatives Employee Foreign Currency Accumulated Other Balance July 1, 2023, net of taxes $ 85 $ (2,483) $ (2,502) $ (4,900) Other comprehensive income (loss) before reclassification adjustments, pretax 247 29 (252) 24 Tax (52) (7) 77 18 Other comprehensive income (loss) before reclassification adjustments, net of taxes 195 22 (175) 42 Reclassification adjustments, pretax (45) (1) (27) (2) — (72) Tax 9 5 — 14 Reclassification adjustments, net of taxes (36) (22) — (58) Other comprehensive income (loss), net of taxes 159 — (175) (16) Balance September 30, 2023, net of taxes $ 244 $ (2,483) $ (2,677) $ (4,916) Balance July 1, 2024, net of taxes $ 173 $ (2,808) $ (2,726) $ (5,361) Other comprehensive income (loss) before reclassification adjustments, pretax (325) — 279 (46) Tax 68 (3) 20 85 Other comprehensive income (loss) before reclassification adjustments, net of taxes (257) (3) 299 39 Reclassification adjustments, pretax (49) (1) (14) (2) — (63) Tax 10 4 — 14 Reclassification adjustments, net of taxes (39) (10) — (49) Other comprehensive income (loss), net of taxes (296) (13) 299 (10) Balance September 30, 2024, net of taxes $ (123) $ (2,821) $ (2,427) $ (5,371) Nine Months Ended September 30, ($ in millions) Derivatives Employee Foreign Currency Accumulated Other Balance January 1, 2023, net of taxes $ 73 $ (2,408) $ (2,433) $ (4,768) Other comprehensive income (loss) before reclassification adjustments, pretax 375 (24) (288) 63 Tax (79) (4) 35 (48) Other comprehensive income (loss) before reclassification adjustments, net of taxes 296 (28) (253) 15 Reclassification adjustments, pretax (158) (1) (57) (2) 9 (206) Tax 33 10 — 43 Reclassification adjustments, net of taxes (125) (47) 9 (163) Other comprehensive income (loss), net of taxes 171 (75) (244) (148) Balance September 30, 2023, net of taxes $ 244 $ (2,483) $ (2,677) $ (4,916) Balance January 1, 2024, net of taxes $ (24) $ (2,793) $ (2,344) $ (5,161) Other comprehensive income (loss) before reclassification adjustments, pretax 22 6 (103) (75) Tax (5) (5) — (10) Other comprehensive income (loss) before reclassification adjustments, net of taxes 17 1 (103) (85) Reclassification adjustments, pretax (147) (1) (44) (2) 20 (171) Tax 31 15 — 46 Reclassification adjustments, net of taxes (116) (29) 20 (125) Other comprehensive income (loss), net of taxes (99) (28) (83) (210) Balance September 30, 2024, net of taxes $ (123) $ (2,821) $ (2,427) $ (5,371) (1) Primarily relates to foreign currency cash flow hedges that were reclassified from AOCL to Sales . (2) Includes net amortization of prior service cost, actuarial gains and losses, settlements and curtailments included in net periodic benefit cost (see Note 10).

Segment Reporting

Segment Reporting	9 Months Ended
	Sep. 30, 2024
Segment Reporting [Abstract]
Segment Reporting	Segment Reporting The Company’s operations are principally managed on a product basis and include two operating segments, Pharmaceutical and Animal Health, both of which are reportable segments. The Pharmaceutical segment includes human health pharmaceutical and vaccine products. Human health pharmaceutical products consist of therapeutic and preventive agents, generally sold by prescription, for the treatment of human disorders. The Company sells these human health pharmaceutical products primarily to drug wholesalers and retailers, hospitals, government agencies and managed health care providers such as health maintenance organizations, pharmacy benefit managers and other institutions. Human health vaccine products consist of preventive pediatric, adolescent and adult vaccines. The Company sells these human health vaccines primarily to physicians, wholesalers, distributors and government entities. A large component of pediatric and adolescent vaccine sales are made to the U.S. Centers for Disease Control and Prevention Vaccines for Children program, which is funded by the U.S. government. Additionally, the Company sells vaccines to the Federal government for placement into vaccine stockpiles. The Animal Health segment discovers, develops, manufactures and markets a wide range of veterinary pharmaceutical and vaccine products, as well as health management solutions and services, for the prevention, treatment and control of disease in all major livestock and companion animal species. The Company also offers an extensive suite of digitally connected identification, traceability and monitoring products. The Company sells its products to veterinarians, distributors, animal producers, farmers and pet owners. Sales of the Company’s products were as follows: Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 ($ in millions) U.S. Int’l Total U.S. Int’l Total U.S. Int’l Total U.S. Int’l Total Pharmaceutical: Oncology Keytruda $ 4,500 $ 2,929 $ 7,429 $ 3,795 $ 2,543 $ 6,338 $ 13,031 $ 8,614 $ 21,646 $ 11,142 $ 7,261 $ 18,403 Alliance revenue-Lynparza (1) 161 177 337 153 146 299 449 498 947 439 445 884 Alliance revenue-Lenvima (1) 173 78 251 160 100 260 523 233 755 476 258 734 Welireg 127 12 139 51 3 54 320 29 349 141 6 146 Alliance revenue-Reblozyl (2) 82 18 100 43 10 52 215 45 261 108 33 142 Vaccines Gardasil/Gardasil 9 1,020 1,285 2,306 838 1,746 2,585 2,045 4,988 7,032 1,718 5,297 7,015 ProQuad/M-M-R II /Varivax 572 131 703 567 146 713 1,500 391 1,891 1,435 388 1,823 Vaxneuvance 137 103 239 182 33 214 397 251 647 423 65 488 RotaTeq 131 62 193 108 48 156 388 185 572 381 203 584 Pneumovax 23 19 49 68 42 98 140 36 152 188 105 223 327 Hospital Acute Care Bridion 339 81 420 265 159 424 1,020 296 1,315 841 572 1,413 Prevymis 101 107 208 70 87 157 265 305 570 186 244 430 Dificid 83 13 96 69 5 74 231 30 261 199 16 215 Zerbaxa 39 26 64 29 24 53 106 77 182 86 71 157 Noxafil 1 40 41 4 47 51 9 132 141 29 138 167 Cardiovascular Alliance revenue-Adempas/Verquvo (3) 96 7 102 96 (4) 92 283 22 306 249 10 259 Adempas — 72 72 — 65 65 — 214 214 — 189 189 Winrevair 147 3 149 — — — 216 3 219 — — — Virology Lagevrio 84 299 383 — 640 640 144 699 843 — 1,236 1,236 Isentress/Isentress HD 54 48 102 58 61 119 147 155 302 165 212 377 Delstrigo 15 50 65 13 40 54 42 139 180 37 110 148 Pifeltro 31 12 42 27 10 37 86 37 123 78 31 109 Neuroscience Belsomra 20 58 78 23 35 58 53 124 177 60 117 176 Immunology Simponi — 189 189 — 179 179 — 545 545 — 539 539 Remicade — 41 41 — 45 45 — 115 115 — 144 144 Diabetes Januvia 67 211 278 328 252 581 428 674 1,102 842 800 1,642 Janumet 15 190 204 43 211 255 70 610 679 182 755 937 Other pharmaceutical (4) 213 426 644 189 381 568 559 1,232 1,796 518 1,239 1,758 Total Pharmaceutical segment sales 8,227 6,717 14,943 7,153 7,110 14,263 22,563 20,795 43,358 19,840 20,602 40,442 Animal Health: Livestock 194 692 886 205 669 874 529 2,044 2,573 543 1,987 2,530 Companion Animal 293 307 601 257 269 526 888 1,019 1,907 875 942 1,817 Total Animal Health segment sales 487 999 1,487 462 938 1,400 1,417 3,063 4,480 1,418 2,929 4,347 Total segment sales 8,714 7,716 16,430 7,615 8,048 15,663 23,980 23,858 47,838 21,258 23,531 44,789 Other (5) 22 206 227 100 199 299 109 597 706 135 561 696 $ 8,736 $ 7,922 $ 16,657 $ 7,715 $ 8,247 $ 15,962 $ 24,089 $ 24,455 $ 48,544 $ 21,393 $ 24,092 $ 45,485 U.S. plus international may not equal total due to rounding. (1) Alliance revenue for Lynparza and Lenvima represents Merck’s share of profits, which are product sales net of cost of sales and commercialization costs (see Note 3). (2) Alliance revenue for Reblozyl represents royalties (see Note 3). (3) Alliance revenue for Adempas/Verquvo represents Merck’s share of profits from sales in Bayer’s marketing territories, which are product sales net of cost of sales and commercialization costs (see Note 3). (4) Other pharmaceutical primarily reflects sales of other human health pharmaceutical products, including products within the franchises not listed separately. (5) Other is primarily comprised of miscellaneous corporate revenue, including revenue hedging activities which increased sales by $156 million and $173 million for the nine months ended September 30, 2024 and 2023, respectively, as well as revenue from third-party manufacturing arrangements (including sales to Organon as discussed in Note 2). Other for the nine months ended September 30, 2024 and 2023 also includes $91 million and $118 million, respectively, related to upfront and milestone payments received by Merck for out-licensing arrangements. Product sales are recorded net of the provision for discounts, including chargebacks, which are customer discounts that occur when a contracted customer purchases through an intermediary wholesale purchaser, and rebates that are owed based upon definitive contractual agreements or legal requirements with private sector and public sector (Medicaid and Medicare Part D) benefit providers, after the final dispensing of the product by a pharmacy to a benefit plan participant. These discounts, in the aggregate, reduced U.S. sales by $3.6 billion and $3.1 billion for the three months ended September 30, 2024 and 2023, respectively, and $10.1 billion and $9.4 billion for the nine months ended September 30, 2024 and September 30, 2023, respectively. Consolidated sales by geographic area where derived are as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 United States $ 8,736 $ 7,715 $ 24,089 $ 21,393 Europe, Middle East and Africa 3,583 3,327 10,661 9,978 China 1,017 1,694 4,606 5,322 Latin America 936 895 2,591 2,298 Japan 938 1,081 2,445 2,514 Asia Pacific (other than China and Japan) 823 781 2,294 2,475 Other 624 469 1,858 1,505 $ 16,657 $ 15,962 $ 48,544 $ 45,485 A reconciliation of segment profits to Income Before Taxes is as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Segment profits: Pharmaceutical segment $ 11,547 $ 10,407 $ 33,651 $ 29,400 Animal Health segment 510 421 1,574 1,453 Total segment profits 12,057 10,828 35,225 30,853 Other profits 117 190 391 374 Unallocated: Interest income 127 73 269 295 Interest expense (330) (317) (943) (836) Amortization (633) (562) (1,720) (1,582) Depreciation (467) (401) (1,368) (1,175) Research and development (5,716) (3,183) (12,926) (20,523) Restructuring costs (56) (126) (258) (344) Charge for Zetia antitrust litigation settlements — — — (573) Other unallocated, net (1,009) (882) (2,904) (2,554) $ 4,090 $ 5,620 $ 15,766 $ 3,935 Pharmaceutical segment profits are comprised of segment sales less standard costs, as well as selling, general and administrative expenses directly incurred by the segment. Animal Health segment profits are comprised of segment sales, less all cost of sales, as well as selling, general and administrative expenses and research and development costs directly incurred by the segment. For internal management reporting presented to the chief operating decision maker, Merck does not allocate the remaining cost of sales not included in segment profits as described above, research and development expenses incurred by Merck Research Laboratories, the Company’s research and development division that focuses on human health-related activities, or general and administrative expenses not directly incurred by the segments, nor the cost of financing these activities. Separate divisions maintain responsibility for monitoring and managing these costs, including depreciation related to fixed assets utilized by these divisions and, therefore, they are not included in segment profits. In addition, costs related to restructuring activities, as well as the amortization of intangible assets and amortization of purchase accounting adjustments are not allocated to segments. Other profits are primarily comprised of miscellaneous corporate profits, as well as operating profits (losses) related to third-party manufacturing arrangements. Other unallocated, net, includes expenses from corporate and manufacturing cost centers, intangible asset impairment charges, gains or losses on sales of businesses, expense or income related to changes in the estimated fair value measurement of liabilities for contingent consideration, and other miscellaneous income or expense items.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Pay vs Performance Disclosure
Net Income Attributable to Merck & Co., Inc.	$ 3,157	$ 4,745	$ 13,374	$ 1,591

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Sep. 30, 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 (Policies

Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements of Merck & Co., Inc. (Merck or the Company) have been prepared pursuant to the rules and regulations for reporting on Form 10-Q. Accordingly, certain information and disclosures required by accounting principles generally accepted in the United States (U.S.) for complete consolidated financial statements are not included herein. These interim statements should be read in conjunction with the audited financial statements and notes thereto included in Merck’s Form 10-K filed on February 26, 2024.
Reclassifications	Certain reclassifications have been made to prior year amounts to conform to the current year presentation.
Recently Adopted Accounting Standard & Recently Issued Accounting Standards Not Yet Adopted	Recently Adopted Accounting Standard In August 2023, the Financial Accounting Standards Board (FASB) issued amended guidance that requires a newly formed joint venture to recognize and initially measure its assets and liabilities at fair value upon formation. The amended guidance includes exceptions to fair value measurement that are consistent with the accounting for business combinations guidance. The amended guidance is effective prospectively for all joint ventures with a formation date on or after January 1, 2025, however existing joint ventures have the option to apply the guidance retrospectively. The Company adopted the guidance effective July 1, 2024 on a prospective basis. There was no impact to the Company’s consolidated financial statements upon adoption. Recently Issued Accounting Standards Not Yet Adopted In November 2023, the FASB issued guidance intended to improve reportable segment disclosure requirements, primarily through expanded disclosures for significant segment expenses. The guidance is effective for annual periods beginning in 2024, and interim periods beginning in 2025. The guidance will result in incremental disclosures within the footnotes to the Company’s financial statements.
Legal Costs	Legal defense costs expected to be incurred in connection with a loss contingency are accrued when probable and reasonably estimable.

Acquisitions, Divestitures, R_2

Acquisitions, Divestitures, Research Collaborations and Licensing Agreements (Tables)	9 Months Ended
	Sep. 30, 2024
Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]
Estimated Fair Value of Assets Acquired and Liabilities Assumed	The estimated fair values of assets acquired and liabilities assumed from the Elanco aqua business (which are considered preliminary subject to the finalization of the tax treatment of the transaction) are as follows: ($ in millions) July 9, 2024 Inventories $ 74 Property, plant and equipment 67 Product rights - Clynav (useful life 15 years) (1) 340 Other product rights (useful lives 15 years) (1) 291 Other assets and liabilities, net 24 Total identifiable net assets 796 Goodwill (2) 505 Consideration transferred $ 1,301 (1) The estimated fair values of Clynav and other product rights were determined using an income approach, specifically the multi-period excess earnings method. The future probability-weighted net cash flows were discounted to present value utilizing a discount rate of 8.5%. Actual cash flows are likely to be different than those assumed. (2)

Collaborative Arrangements (Tab

Collaborative Arrangements (Tables)	9 Months Ended
	Sep. 30, 2024
Collaborative Arrangements [Abstract]
Collaboration Arrangements	Summarized financial information related to this collaboration is as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Alliance revenue - Lynparza $ 337 $ 299 $ 947 $ 884 Alliance revenue - Koselugo 39 26 114 74 Total alliance revenue $ 376 $ 325 $ 1,061 $ 958 Cost of sales (1) 82 82 245 230 Selling, general and administrative 39 44 121 143 Research and development 19 23 57 65 ($ in millions) September 30, 2024 December 31, 2023 Receivables from AstraZeneca included in Other current assets $ 375 $ 341 Payables to AstraZeneca included in Accrued and other current liabilities (2) 615 256 Payables to AstraZeneca included in Other Noncurrent Liabilities (2) — 600 (1) Represents amortization of capitalized milestone payments. (2) Includes accrued milestone payments. Summarized financial information related to this collaboration is as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Alliance revenue - Lenvima $ 251 $ 260 $ 755 $ 734 Cost of sales (1) 60 137 181 320 Selling, general and administrative 40 46 120 145 Research and development 4 5 18 61 ($ in millions) September 30, 2024 December 31, 2023 Receivables from Eisai included in Other current assets $ 252 $ 226 Payables to Eisai included in Accrued and other current liabilities (2) — 125 (1) Represents amortization of capitalized milestone payments. Amounts in the third quarter and first nine months of 2023 include $81 million and $154 million, respectively, of cumulative amortization catch-up expense as noted above. (2) Represents an accrued milestone payment. Summarized financial information related to this collaboration is as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Alliance revenue - Adempas/Verquvo $ 102 $ 92 $ 306 $ 259 Net sales of Adempas recorded by Merck 72 65 214 189 Net sales of Verquvo recorded by Merck 11 8 25 24 Total sales $ 185 $ 165 $ 545 $ 472 Cost of sales (1) 59 53 182 165 Selling, general and administrative 29 33 88 100 Research and development 27 26 82 76 ($ in millions) September 30, 2024 December 31, 2023 Receivables from Bayer included in Other current assets $ 166 $ 156 Payables to Bayer included in Accrued and other current liabilities 82 80 (1) Includes amortization of intangible assets, cost of products sold by Merck, as well as Bayer’s share of profits from sales in Merck’s marketing territories. Summarized financial information related to this collaboration is as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Net sales of Lagevrio recorded by Merck $ 383 $ 640 $ 843 $ 1,236 Cost of sales (1) 204 348 491 762 Selling, general and administrative 11 21 43 72 Research and development 5 8 7 33 ($ in millions) September 30, 2024 December 31, 2023 Payables to Ridgeback included in Accrued and other current liabilities (2) $ 176 $ 113 (1) Includes cost of products sold by Merck, Ridgeback’s share of profits, royalty expense, amortization of capitalized milestone payments and inventory reserves. (2) Includes accrued royalties. Summarized financial information related to this collaboration is as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Selling, general and administrative $ 5 $ — $ 21 $ — Research and development 94 — 227 — ($ in millions) September 30, 2024 December 31, 2023 Payables to Daiichi Sankyo included in Accrued and other current liabilities $ 811 $ 800 Payables to Daiichi Sankyo included in Other Noncurrent Liabilities 750 750 Summarized financial information related to this collaboration is as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Selling, general and administrative $ 5 $ 2 $ 11 $ 3 Research and development 93 66 255 153 ($ in millions) September 30, 2024 December 31, 2023 Payables to Moderna included in Accrued and other current liabilities $ 68 $ 63

Restructuring (Tables)

Restructuring (Tables)	9 Months Ended
	Sep. 30, 2024
Restructuring and Related Activities [Abstract]
Charges Related to Restructuring Program Activities by Type of Cost	The following tables summarize the charges related to the restructuring programs by type of cost: Three Months Ended September 30, 2024 Nine Months Ended September 30, 2024 ($ in millions) Accelerated Depreciation Separation Costs Other Exit Costs Total Accelerated Depreciation Separation Costs Other Total 2024 Restructuring Program Cost of sales $ 40 $ — $ 152 $ 192 $ 171 $ — $ 203 $ 374 Selling, general and administrative — — 31 31 — — 67 67 Research and development — — — — — — 2 2 Restructuring costs — 11 45 56 — 122 136 258 $ 40 $ 11 $ 228 $ 279 $ 171 $ 122 $ 408 $ 701 Three Months Ended September 30, 2023 Nine Months Ended September 30, 2023 ($ in millions) Accelerated Depreciation Separation Costs Other Exit Costs Total Accelerated Depreciation Separation Costs Other Total 2019 Restructuring Program Cost of sales $ 31 $ — $ 2 $ 33 $ 74 $ — $ 20 $ 94 Selling, general and administrative 5 — 35 40 5 — 88 93 Research and development — — — — — — 1 1 Restructuring costs — 95 31 126 — 246 98 344 $ 36 $ 95 $ 68 $ 199 $ 79 $ 246 $ 207 $ 532
Charges and Spending Relating to Restructuring Activities by Program	The following table summarizes the charges and spending relating to restructuring program activities for the nine months ended September 30, 2024: ($ in millions) Accelerated Depreciation Separation Costs Other Exit Costs Total Restructuring reserves January 1, 2024 $ — $ 681 $ 31 $ 712 Expenses 171 122 408 701 (Payments) receipts, net — (177) (122) (299) Non-cash activity (171) — (292) (463) Restructuring reserves September 30, 2024 $ — $ 626 $ 25 $ 651

Financial Instruments (Tables)

Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Effect of Net Investment Hedges on OCI and the Consolidated Statement of Operations	The effects of the Company’s net investment hedges on OCI and the Condensed Consolidated Statement of Income are shown below: Amount of Pretax (Gain) Loss Recognized in Other Comprehensive Income (1) Amount of Pretax (Gain) Loss Recognized in Other (income) expense, net for Amounts Excluded from Effectiveness Testing Three Months Ended September 30, Nine Months Ended September 30, Three Months Ended September 30, Nine Months Ended September 30, ($ in millions) 2024 2023 2024 2023 2024 2023 2024 2023 Net Investment Hedging Relationships Foreign exchange contracts $ 1 $ (1) $ 4 $ — $ — $ — $ (2) $ 1 Euro-denominated notes 169 (100) 73 (26) — — — — (1) No amounts were reclassified from AOCL into income related to the sale of a subsidiary.
Summary of Interest Rate Swaps Held	At September 30, 2024, the Company was a party to six pay-floating, receive-fixed interest rate swap contracts designated as fair value hedges of a portion of fixed-rate notes as detailed in the table below. September 30, 2024 ($ in millions) Par Value of Debt Number of Interest Rate Swaps Held Total Swap Notional Amount 4.50% notes due 2033 $ 1,500 6 $ 1,500
Amounts Recorded on Balance Sheet Related to Fair Value Hedges	The table below presents the location of amounts recorded in the Condensed Consolidated Balance Sheet related to cumulative basis adjustments for fair value hedges: Carrying Amount of Hedged Liabilities Cumulative Amount of Fair Value Hedging Adjustment Increase Included in the Carrying Amount ($ in millions) September 30, 2024 December 31, 2023 September 30, 2024 December 31, 2023 Balance Sheet Caption Long-Term Debt $ 1,589 $ 1,056 $ 98 $ 56
Fair Value of Derivatives on a Gross Basis Segregated between those Derivatives that are Designated as Hedging Instruments and those that are Not Designated as Hedging Instruments	Presented in the table below is the fair value of derivatives on a gross basis segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments: September 30, 2024 December 31, 2023 Fair Value of Derivative U.S. Dollar Fair Value of Derivative U.S. Dollar ($ in millions) Asset Liability Asset Liability Derivatives Designated as Hedging Instruments Balance Sheet Caption Interest rate swap contracts Other Assets $ 99 $ — $ 1,500 $ 57 $ — $ 1,000 Foreign exchange contracts Other current assets 30 — 4,635 106 — 6,138 Foreign exchange contracts Other Assets 28 — 2,170 26 — 1,929 Foreign exchange contracts Accrued and other current liabilities — 118 5,022 — 76 3,680 Foreign exchange contracts Other Noncurrent Liabilities — 1 54 — 1 7 157 119 13,381 189 77 12,754 Derivatives Not Designated as Hedging Instruments Balance Sheet Caption Foreign exchange contracts Other current assets 183 — 10,298 153 — 9,693 Foreign exchange contracts Accrued and other current liabilities — 179 11,635 — 162 8,104 183 179 21,933 153 162 17,797 $ 340 $ 298 $ 35,314 $ 342 $ 239 $ 30,551
Information on Derivative Positions Subject to Master Netting Arrangements as if they were Presented on a Net Basis	The following table provides information on the Company’s derivative positions subject to these master netting arrangements as if they were presented on a net basis, allowing for the right of offset by counterparty and cash collateral exchanged per the master agreements and related credit support annexes: September 30, 2024 December 31, 2023 ($ in millions) Asset Liability Asset Liability Gross amounts recognized in the condensed consolidated balance sheet $ 340 $ 298 $ 342 $ 239 Gross amounts subject to offset in master netting arrangements not offset in the condensed consolidated balance sheet (225) (225) (215) (215) Cash collateral received — — (3) — Net amounts $ 115 $ 73 $ 124 $ 24
Location and Amount of Pretax Gains and Losses of Derivatives	The table below provides information regarding the location and amount of pretax gains and losses of derivatives designated in fair value or cash flow hedging relationships: Three Months Ended September 30, Nine Months Ended September 30, ($ in millions) 2024 2023 2024 2023 2024 2023 2024 2023 2024 2023 2024 2023 Financial Statement Caption in which Effects of Fair Value or Cash Flow Sales Other (income) expense, net (1) Other comprehensive income (loss) Sales Other (income) expense, net (1) Other comprehensive income (loss) $ 16,657 $ 15,962 $ (162) $ 126 $ (10) $ (16) $ 48,544 $ 45,485 $ (151) $ 388 $ (210) $ (148) Loss (gain) on fair value hedging relationships: Interest rate swap contracts Hedged items — — 68 (7) — — — — 42 (7) — — Derivatives designated as hedging instruments — — (69) 8 — — — — (43) 8 — — Impact of cash flow hedging relationships: Foreign exchange contracts Amount of (loss) gain recognized in OCI on derivatives — — — — (325) 247 — — — — 22 375 Increase in Sales as a result of AOCL reclassifications 48 45 — — (48) (45) 146 170 — — (146) (170) Interest rate contracts Amount of gain recognized in Other (income) expense, net on derivatives — — — — — — — — (1) (1) — — Amount of (loss) gain recognized in OCI on derivatives — — — — — — — — — — (1) 13 (1) Interest expense is a component of Other (income) expense, net.
Income Statement Effects of Derivatives Not Designated as Hedging Instruments	The table below provides information regarding the income statement effects of derivatives not designated as hedging instruments: Amount of Derivative Pretax (Gain) Loss Recognized in Income Three Months Ended September 30, Nine Months Ended September 30, ($ in millions) 2024 2023 2024 2023 Derivatives Not Designated as Hedging Instruments Income Statement Caption Foreign exchange contracts (1) Other (income) expense, net $ (139) $ 60 $ (65) $ 32 Foreign exchange contracts (2) Sales 10 — (10) (3) (1) These derivative contracts primarily mitigate changes in the value of remeasured foreign currency denominated monetary assets and liabilities attributable to changes in foreign currency exchange rates. (2) These derivative contracts serve as economic hedges of forecasted transactions .
Information on Investments in Debt and Equity Securities	Information on investments in debt and equity securities is as follows: September 30, 2024 December 31, 2023 Amortized Gross Unrealized Fair Amortized Gross Unrealized Fair ($ in millions) Gains Losses Gains Losses U.S. government and agency securities $ 81 $ — $ — $ 81 $ 72 $ — $ — $ 72 Commercial paper — — — — 252 — — 252 Corporate notes and bonds — — — — 13 — — 13 Total debt securities $ 81 $ — $ — $ 81 $ 337 $ — $ — $ 337 Publicly traded equity securities (1) 984 764 Total debt and publicly traded equity securities $ 1,065 $ 1,101 (1) Unrealized net losses (gains) of $42 million and $(82) million were recorded in Other (income) expense, net in the third quarter and first nine months of 2024, respectively, on equity securities still held at September 30, 2024. Unrealized net gains of $61 million and $327 million were recorded in Other (income) expense, net in the third quarter and first nine months of 2023, respectively, on equity securities still held at September 30, 2023.
Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis	Financial assets and liabilities measured at fair value on a recurring basis are summarized below: Fair Value Measurements Using Fair Value Measurements Using Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total ($ in millions) September 30, 2024 December 31, 2023 Assets Investments Commercial paper $ — $ — $ — $ — $ — $ 252 $ — $ 252 Publicly traded equity securities 575 — — 575 252 — — 252 575 — — 575 252 252 — 504 Other assets (1) U.S. government and agency securities 81 — — 81 72 — — 72 Corporate notes and bonds — — — — 13 — — 13 Publicly traded equity securities 409 — — 409 512 — — 512 490 — — 490 597 — — 597 Derivative assets (2) Forward exchange contracts — 180 — 180 — 202 — 202 Interest rate swaps — 99 — 99 — 57 — 57 Purchased currency options — 61 — 61 — 83 — 83 — 340 — 340 — 342 — 342 Total assets $ 1,065 $ 340 $ — $ 1,405 $ 849 $ 594 $ — $ 1,443 Liabilities Other liabilities Contingent consideration $ — $ — $ 208 $ 208 $ — $ — $ 354 $ 354 Derivative liabilities (2) Forward exchange contracts — 291 — 291 — 239 — 239 Written currency options — 7 — 7 — — — — — 298 — 298 — 239 — 239 Total liabilities $ — $ 298 $ 208 $ 506 $ — $ 239 $ 354 $ 593 (1) Investments included in other assets are restricted as to use, including for the payment of benefits under employee benefit plans. (2) The fair value determination of derivatives includes the impact of the credit risk of counterparties to the derivatives and the Company’s own credit risk, the effects of which were not significant.
Information About the Changes in Liabilities for Contingent Consideration	Summarized information about the changes in the fair value of liabilities for contingent consideration associated with business combinations is as follows: ($ in millions) 2024 2023 Fair value January 1 $ 354 $ 456 Changes in estimated fair value (1) 2 6 Payments (148) (117) Fair value September 30 (2) $ 208 $ 345 (1) Recorded in Cost of sales, Research and development expenses, and Other (income) expense, net . Includes cumulative translation adjustments. (2) Balance at September 30, 2024, includes $163 million of current liabilities, of which $136 million relates to the termination of the Sanofi Pasteur MSD joint venture in 2016. As part of the termination, Merck recorded a liability for contingent future royalty payments of 11.5% on net sales of all Merck products that were previously sold by the joint venture through December 31, 2024. The fair value of this liability is determined utilizing the estimated amount and timing of projected cash flows using a risk-adjusted discount rate to present value the cash flows.

Inventories (Tables)

Inventories (Tables)	9 Months Ended
	Sep. 30, 2024
Inventory Disclosure [Abstract]
Inventory, current	Inventories consisted of: ($ in millions) September 30, 2024 December 31, 2023 Finished goods $ 1,939 $ 1,954 Raw materials and work in process 8,780 8,037 Supplies 282 277 Total 11,001 10,268 Decrease to LIFO cost (762) (562) $ 10,239 $ 9,706 Recognized as: Inventories $ 6,244 $ 6,358 Other Assets 3,995 3,348
Inventory, noncurrent	Inventories consisted of: ($ in millions) September 30, 2024 December 31, 2023 Finished goods $ 1,939 $ 1,954 Raw materials and work in process 8,780 8,037 Supplies 282 277 Total 11,001 10,268 Decrease to LIFO cost (762) (562) $ 10,239 $ 9,706 Recognized as: Inventories $ 6,244 $ 6,358 Other Assets 3,995 3,348

Equity (Tables)

Equity (Tables)	9 Months Ended
	Sep. 30, 2024
Equity [Abstract]
Schedule of Equity	Three Months Ended September 30, Common Stock Other Retained Accumulated Treasury Stock Non- Total ($ and shares in millions except per share amounts) Shares Par Value Shares Cost Balance at July 1, 2023 3,577 $ 1,788 $ 44,219 $ 54,198 $ (4,900) 1,038 $ (56,612) $ 49 $ 38,742 Net income attributable to Merck & Co., Inc. — — — 4,745 — — — — 4,745 Other comprehensive loss, net of taxes — — — — (16) — — — (16) Cash dividends declared on common stock ($0.73 per share) — — — (1,861) — — — — (1,861) Treasury stock shares purchased — — — — — 4 (466) — (466) Share-based compensation plans and other — — 139 — — — 12 — 151 Net income attributable to noncontrolling interests — — — — — — — 5 5 Balance at September 30, 2023 3,577 $ 1,788 $ 44,358 $ 57,082 $ (4,916) 1,042 $ (57,066) $ 54 $ 41,300 Balance at July 1, 2024 3,577 $ 1,788 $ 44,362 $ 60,187 $ (5,361) 1,041 $ (57,394) $ 66 $ 43,648 Net income attributable to Merck & Co., Inc. — — — 3,157 — — — — 3,157 Other comprehensive loss, net of taxes — — — — (10) — — — (10) Cash dividends declared on common stock ($0.77 per share) — — — (1,960) — — — — (1,960) Treasury stock shares purchased — — — — — 4 (444) — (444) Share-based compensation plans and other — — 168 — — — 9 — 177 Net income attributable to noncontrolling interests — — — — — — — 4 4 Distributions attributable to noncontrolling interests — — — — — — — (12) (12) Balance at September 30, 2024 3,577 $ 1,788 $ 44,530 $ 61,384 $ (5,371) 1,045 $ (57,829) $ 58 $ 44,560 Nine Months Ended September 30, Common Stock Other Retained Accumulated Treasury Stock Non- Total ($ and shares in millions except per share amounts) Shares Par Value Shares Cost Balance at January 1, 2023 3,577 $ 1,788 $ 44,379 $ 61,081 $ (4,768) 1,039 $ (56,489) $ 67 $ 46,058 Net income attributable to Merck & Co., Inc. — — — 1,591 — — — — 1,591 Other comprehensive loss, net of taxes — — — — (148) — — — (148) Cash dividends declared on common stock ($2.19 per share) — — — (5,590) — — — — (5,590) Treasury stock shares purchased — — — — — 9 (953) — (953) Share-based compensation plans and other — — (21) — — (6) 376 — 355 Net income attributable to noncontrolling interests — — — — — — — 12 12 Distributions attributable to noncontrolling interests — — — — — — — (25) (25) Balance at September 30, 2023 3,577 $ 1,788 $ 44,358 $ 57,082 $ (4,916) 1,042 $ (57,066) $ 54 $ 41,300 Balance at January 1, 2024 3,577 $ 1,788 $ 44,509 $ 53,895 $ (5,161) 1,045 $ (57,450) $ 54 $ 37,635 Net income attributable to Merck & Co., Inc. — — — 13,374 — — — — 13,374 Other comprehensive loss, net of taxes — — — — (210) — — — (210) Cash dividends declared on common stock ($2.31 per share) — — — (5,885) — — — — (5,885) Treasury stock shares purchased — — — — — 7 (817) — (817) Share-based compensation plans and other — — 21 — — (7) 438 1 460 Net income attributable to noncontrolling interests — — — — — — — 15 15 Distributions attributable to noncontrolling interests — — — — — — — (12) (12) Balance at September 30, 2024 3,577 $ 1,788 $ 44,530 $ 61,384 $ (5,371) 1,045 $ (57,829) $ 58 $ 44,560

Pension and Other Postretirem_2

Pension and Other Postretirement Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2024
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Net Benefit Costs	The Company has defined benefit pension plans covering eligible employees in the U.S. and in certain of its international subsidiaries. The net periodic benefit cost (credit) of such plans consisted of the following components: Three Months Ended Nine Months Ended 2024 2023 2024 2023 ($ in millions) U.S. International U.S. International U.S. International U.S. International Service cost $ 100 $ 60 $ 88 $ 48 $ 273 $ 182 $ 239 $ 148 Interest cost 134 74 130 76 403 220 396 225 Expected return on plan assets (206) (139) (182) (131) (621) (416) (553) (390) Amortization of unrecognized prior service (credit) cost — (3) — (6) — (10) (1) 5 Net loss (gain) amortization 12 1 — (1) 30 4 — (2) Termination benefits 1 — 1 — 5 — 2 — Curtailments — — — — — — 5 — Settlements — — — — — — 26 — $ 41 $ (7) $ 37 $ (14) $ 90 $ (20) $ 114 $ (14)
Other Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Net Benefit Costs	The Company provides medical benefits, principally to its eligible U.S. retirees and similar benefits to their dependents, through its other postretirement benefit plans. The net credit of such plans consisted of the following components: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Service cost $ 7 $ 8 $ 23 $ 24 Interest cost 14 16 42 47 Expected return on plan assets (20) (16) (60) (48) Amortization of unrecognized prior service credit (11) (12) (32) (37) Net gain amortization (14) (11) (38) (31) Curtailments — — — (1) $ (24) $ (15) $ (65) $ (46)

Other (Income) Expense, Net (Ta

Other (Income) Expense, Net (Tables)	9 Months Ended
	Sep. 30, 2024
Other Income and Expenses [Abstract]
Other (Income) Expense, Net	Other (income) expense, net, consisted of: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Interest income $ (127) $ (73) $ (269) $ (295) Interest expense 330 317 943 836 Exchange losses 33 85 177 208 Loss (income) from investments in equity securities, net (1) 31 33 (169) (240) Net periodic defined benefit plan (credit) cost other than service cost (157) (138) (476) (364) Other, net (272) (98) (357) 243 $ (162) $ 126 $ (151) $ 388 (1)

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2024
Earnings Per Share [Abstract]
Calculations of Earnings Per Share	The calculations of earnings per share are as follows: Three Months Ended Nine Months Ended ($ and shares in millions except per share amounts) 2024 2023 2024 2023 Net Income Attributable to Merck & Co., Inc. $ 3,157 $ 4,745 $ 13,374 $ 1,591 Average common shares outstanding 2,534 2,537 2,534 2,538 Common shares issuable (1) 7 9 9 11 Average common shares outstanding assuming dilution 2,541 2,546 2,543 2,549 Basic Earnings per Common Share Attributable to Merck & Co., Inc. Common Shareholders $ 1.25 $ 1.87 $ 5.28 $ 0.63 Earnings per Common Share Assuming Dilution Attributable to Merck & Co., Inc. Common Shareholders $ 1.24 $ 1.86 $ 5.26 $ 0.62 (1) Issuable primarily under share-based compensation plans.

Other Comprehensive Income (L_2

Other Comprehensive Income (Loss) (Tables)	9 Months Ended
	Sep. 30, 2024
Equity [Abstract]
Changes in AOCI by Component	Changes in each component of other comprehensive income (loss) are as follows: Three Months Ended September 30, ($ in millions) Derivatives Employee Foreign Currency Accumulated Other Balance July 1, 2023, net of taxes $ 85 $ (2,483) $ (2,502) $ (4,900) Other comprehensive income (loss) before reclassification adjustments, pretax 247 29 (252) 24 Tax (52) (7) 77 18 Other comprehensive income (loss) before reclassification adjustments, net of taxes 195 22 (175) 42 Reclassification adjustments, pretax (45) (1) (27) (2) — (72) Tax 9 5 — 14 Reclassification adjustments, net of taxes (36) (22) — (58) Other comprehensive income (loss), net of taxes 159 — (175) (16) Balance September 30, 2023, net of taxes $ 244 $ (2,483) $ (2,677) $ (4,916) Balance July 1, 2024, net of taxes $ 173 $ (2,808) $ (2,726) $ (5,361) Other comprehensive income (loss) before reclassification adjustments, pretax (325) — 279 (46) Tax 68 (3) 20 85 Other comprehensive income (loss) before reclassification adjustments, net of taxes (257) (3) 299 39 Reclassification adjustments, pretax (49) (1) (14) (2) — (63) Tax 10 4 — 14 Reclassification adjustments, net of taxes (39) (10) — (49) Other comprehensive income (loss), net of taxes (296) (13) 299 (10) Balance September 30, 2024, net of taxes $ (123) $ (2,821) $ (2,427) $ (5,371) Nine Months Ended September 30, ($ in millions) Derivatives Employee Foreign Currency Accumulated Other Balance January 1, 2023, net of taxes $ 73 $ (2,408) $ (2,433) $ (4,768) Other comprehensive income (loss) before reclassification adjustments, pretax 375 (24) (288) 63 Tax (79) (4) 35 (48) Other comprehensive income (loss) before reclassification adjustments, net of taxes 296 (28) (253) 15 Reclassification adjustments, pretax (158) (1) (57) (2) 9 (206) Tax 33 10 — 43 Reclassification adjustments, net of taxes (125) (47) 9 (163) Other comprehensive income (loss), net of taxes 171 (75) (244) (148) Balance September 30, 2023, net of taxes $ 244 $ (2,483) $ (2,677) $ (4,916) Balance January 1, 2024, net of taxes $ (24) $ (2,793) $ (2,344) $ (5,161) Other comprehensive income (loss) before reclassification adjustments, pretax 22 6 (103) (75) Tax (5) (5) — (10) Other comprehensive income (loss) before reclassification adjustments, net of taxes 17 1 (103) (85) Reclassification adjustments, pretax (147) (1) (44) (2) 20 (171) Tax 31 15 — 46 Reclassification adjustments, net of taxes (116) (29) 20 (125) Other comprehensive income (loss), net of taxes (99) (28) (83) (210) Balance September 30, 2024, net of taxes $ (123) $ (2,821) $ (2,427) $ (5,371) (1) Primarily relates to foreign currency cash flow hedges that were reclassified from AOCL to Sales . (2) Includes net amortization of prior service cost, actuarial gains and losses, settlements and curtailments included in net periodic benefit cost (see Note 10).

Segment Reporting (Tables)

Segment Reporting (Tables)	9 Months Ended
	Sep. 30, 2024
Segment Reporting [Abstract]
Sales from Products	Sales of the Company’s products were as follows: Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 ($ in millions) U.S. Int’l Total U.S. Int’l Total U.S. Int’l Total U.S. Int’l Total Pharmaceutical: Oncology Keytruda $ 4,500 $ 2,929 $ 7,429 $ 3,795 $ 2,543 $ 6,338 $ 13,031 $ 8,614 $ 21,646 $ 11,142 $ 7,261 $ 18,403 Alliance revenue-Lynparza (1) 161 177 337 153 146 299 449 498 947 439 445 884 Alliance revenue-Lenvima (1) 173 78 251 160 100 260 523 233 755 476 258 734 Welireg 127 12 139 51 3 54 320 29 349 141 6 146 Alliance revenue-Reblozyl (2) 82 18 100 43 10 52 215 45 261 108 33 142 Vaccines Gardasil/Gardasil 9 1,020 1,285 2,306 838 1,746 2,585 2,045 4,988 7,032 1,718 5,297 7,015 ProQuad/M-M-R II /Varivax 572 131 703 567 146 713 1,500 391 1,891 1,435 388 1,823 Vaxneuvance 137 103 239 182 33 214 397 251 647 423 65 488 RotaTeq 131 62 193 108 48 156 388 185 572 381 203 584 Pneumovax 23 19 49 68 42 98 140 36 152 188 105 223 327 Hospital Acute Care Bridion 339 81 420 265 159 424 1,020 296 1,315 841 572 1,413 Prevymis 101 107 208 70 87 157 265 305 570 186 244 430 Dificid 83 13 96 69 5 74 231 30 261 199 16 215 Zerbaxa 39 26 64 29 24 53 106 77 182 86 71 157 Noxafil 1 40 41 4 47 51 9 132 141 29 138 167 Cardiovascular Alliance revenue-Adempas/Verquvo (3) 96 7 102 96 (4) 92 283 22 306 249 10 259 Adempas — 72 72 — 65 65 — 214 214 — 189 189 Winrevair 147 3 149 — — — 216 3 219 — — — Virology Lagevrio 84 299 383 — 640 640 144 699 843 — 1,236 1,236 Isentress/Isentress HD 54 48 102 58 61 119 147 155 302 165 212 377 Delstrigo 15 50 65 13 40 54 42 139 180 37 110 148 Pifeltro 31 12 42 27 10 37 86 37 123 78 31 109 Neuroscience Belsomra 20 58 78 23 35 58 53 124 177 60 117 176 Immunology Simponi — 189 189 — 179 179 — 545 545 — 539 539 Remicade — 41 41 — 45 45 — 115 115 — 144 144 Diabetes Januvia 67 211 278 328 252 581 428 674 1,102 842 800 1,642 Janumet 15 190 204 43 211 255 70 610 679 182 755 937 Other pharmaceutical (4) 213 426 644 189 381 568 559 1,232 1,796 518 1,239 1,758 Total Pharmaceutical segment sales 8,227 6,717 14,943 7,153 7,110 14,263 22,563 20,795 43,358 19,840 20,602 40,442 Animal Health: Livestock 194 692 886 205 669 874 529 2,044 2,573 543 1,987 2,530 Companion Animal 293 307 601 257 269 526 888 1,019 1,907 875 942 1,817 Total Animal Health segment sales 487 999 1,487 462 938 1,400 1,417 3,063 4,480 1,418 2,929 4,347 Total segment sales 8,714 7,716 16,430 7,615 8,048 15,663 23,980 23,858 47,838 21,258 23,531 44,789 Other (5) 22 206 227 100 199 299 109 597 706 135 561 696 $ 8,736 $ 7,922 $ 16,657 $ 7,715 $ 8,247 $ 15,962 $ 24,089 $ 24,455 $ 48,544 $ 21,393 $ 24,092 $ 45,485 U.S. plus international may not equal total due to rounding. (1) Alliance revenue for Lynparza and Lenvima represents Merck’s share of profits, which are product sales net of cost of sales and commercialization costs (see Note 3). (2) Alliance revenue for Reblozyl represents royalties (see Note 3). (3) Alliance revenue for Adempas/Verquvo represents Merck’s share of profits from sales in Bayer’s marketing territories, which are product sales net of cost of sales and commercialization costs (see Note 3). (4) Other pharmaceutical primarily reflects sales of other human health pharmaceutical products, including products within the franchises not listed separately. (5) Other is primarily comprised of miscellaneous corporate revenue, including revenue hedging activities which increased sales by $156 million and $173 million for the nine months ended September 30, 2024 and 2023, respectively, as well as revenue from third-party manufacturing arrangements (including sales to Organon as discussed in Note 2). Other for the nine months ended September 30, 2024 and 2023 also includes $91 million and $118 million, respectively, related to upfront and milestone payments received by Merck for out-licensing arrangements.
Consolidated Sales by Geographic Area	Consolidated sales by geographic area where derived are as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 United States $ 8,736 $ 7,715 $ 24,089 $ 21,393 Europe, Middle East and Africa 3,583 3,327 10,661 9,978 China 1,017 1,694 4,606 5,322 Latin America 936 895 2,591 2,298 Japan 938 1,081 2,445 2,514 Asia Pacific (other than China and Japan) 823 781 2,294 2,475 Other 624 469 1,858 1,505 $ 16,657 $ 15,962 $ 48,544 $ 45,485
Reconciliation of Segment Profits to Income before Taxes	A reconciliation of segment profits to Income Before Taxes is as follows: Three Months Ended Nine Months Ended ($ in millions) 2024 2023 2024 2023 Segment profits: Pharmaceutical segment $ 11,547 $ 10,407 $ 33,651 $ 29,400 Animal Health segment 510 421 1,574 1,453 Total segment profits 12,057 10,828 35,225 30,853 Other profits 117 190 391 374 Unallocated: Interest income 127 73 269 295 Interest expense (330) (317) (943) (836) Amortization (633) (562) (1,720) (1,582) Depreciation (467) (401) (1,368) (1,175) Research and development (5,716) (3,183) (12,926) (20,523) Restructuring costs (56) (126) (258) (344) Charge for Zetia antitrust litigation settlements — — — (573) Other unallocated, net (1,009) (882) (2,904) (2,554) $ 4,090 $ 5,620 $ 15,766 $ 3,935

Acquisitions, Divestitures, R_3

Acquisitions, Divestitures, Research Collaborations and Licensing Agreements - Narrative (Details) $ in Millions		1 Months Ended					3 Months Ended			9 Months Ended
	Jun. 02, 2021	Sep. 30, 2024 USD ($) jurisdiction	Jul. 31, 2024 USD ($) candidate aqua_facility	Mar. 31, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jan. 31, 2023 USD ($)	Sep. 30, 2024 USD ($) jurisdiction	Dec. 31, 2023 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) jurisdiction	Sep. 30, 2023 USD ($)	Apr. 30, 2024 candidate	Oct. 31, 2023 USD ($) candidate	Feb. 28, 2023 candidate
Business Acquisition [Line Items]
Research and development							$ 5,862		$ 3,307	$ 13,354	$ 20,904
Sales							16,657		15,962	48,544	45,485
Cost of sales							4,080		4,264	11,365	12,214
Other current assets		$ 8,143					8,143	$ 8,368		8,143
Accrued and other current liabilities		16,539					16,539	15,766		16,539
Related Party
Business Acquisition [Line Items]
Other current assets		370					370	632		370
Accrued and other current liabilities		$ 130					130	598		130
Manufacturing and Supply Agreements | Related Party
Business Acquisition [Line Items]
Sales							109		100	309	290
Cost of sales							$ 108		106	$ 310	314
Minimum | Manufacturing and Supply Agreements | Related Party
Business Acquisition [Line Items]
Period of continuing involvement after disposal	4 years
Maximum | Manufacturing and Supply Agreements | Related Party
Business Acquisition [Line Items]
Period of continuing involvement after disposal	10 years
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff | Organon & Co.
Business Acquisition [Line Items]
Number of jurisdictions remaining | jurisdiction		1					1			1
Orion
Business Acquisition [Line Items]
Eligible future contingent development-related payments (up to)			$ 30
Eligible future contingent regulatory milestone payments (up to)			625
Eligible future contingent sales-based milestone payments (up to)			$ 975
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Business Acquisition [Line Items]
Research and development							$ 94	5,500	0	$ 227	0
Number of antibody drug conjugates obtained right and obligations | candidate													3
Accrued and other current liabilities		$ 811					811	$ 800		811
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Business Acquisition [Line Items]
Eligible future contingent development-related payments (up to)													$ 540
Eligible future contingent regulatory milestone payments (up to)													1,500
Eligible future contingent sales-based milestone payments (up to)													$ 3,100
Number of antibody drug conjugates | candidate														7
Upfront payment made to collaborative partner									$ 175		175
Number of antibody drug conjugates terminated | candidate												1	2
Number of exercised license option antibody drug conjugates | candidate			1
Number of licensed antibody drug conjugates | candidate			3
Number of unexercised license option antibody drug conjugates | candidate			1
Payment resulting from the license option exercise			$ 38
Stock investment in counterparty						$ 100
Elanco Animal Health Incorporated Aqua Business
Business Acquisition [Line Items]
Payment to acquire business			$ 1,300
Aqua manufacturing facilities | aqua_facility			2
CN201, Curon Biopharmaceutical
Business Acquisition [Line Items]
Consideration transferred, asset acquisition		700
Future contingent developmental milestone payments (up to)		300					300			300
Future regulatory milestone payments (up to)		300					300			300
Research and development							750			750
CN201, Curon Biopharmaceutical | Third-Party
Business Acquisition [Line Items]
Aggregate contingent developmental, regulatory, and sales-based-related payments		$ 128					128			128
Eyebiotech Limited
Business Acquisition [Line Items]
Consideration transferred, asset acquisition			$ 1,200
Future contingent developmental milestone payments (up to)			200
Future regulatory milestone payments (up to)			1,000
Research and development							1,350			1,350
Asset acquisition, transaction costs			207
Developmental milestone payment triggered							100
Maximum aggregate sales-based milestone payments			$ 500
Net assets acquired							$ 21			21
Harpoon Therapeutics, Inc.
Business Acquisition [Line Items]
Consideration transferred, asset acquisition				$ 765
Research and development										656
Asset acquisition, transaction costs				$ 56
Net assets acquired										$ 165
Prometheus Biosciences, Inc.
Business Acquisition [Line Items]
Consideration transferred, asset acquisition					$ 11,000
Research and development											10,200
Net assets acquired					877
Consideration transferred, to settle share-based equity awards					1,200
Consideration transferred, to settle equity awards, unvested					700
Cash recorded for asset acquisition					368
Investments recorded for asset acquisition					296
Deferred tax assets recorded for asset acquisition					218
Other net liabilities recorded for asset acquisition					$ 5
Imago Bio Sciences, Inc.
Business Acquisition [Line Items]
Consideration transferred, asset acquisition						1,350
Research and development											$ 1,200
Asset acquisition, transaction costs						60
Net assets acquired						$ 219

Acquisitions, Divestitures, R_4

Acquisitions, Divestitures, Research Collaborations and Licensing Agreements - Estimated Fair Value of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Millions	Sep. 30, 2024	Jul. 09, 2024	Dec. 31, 2023
Business Acquisition [Line Items]
Goodwill	$ 21,697		$ 21,197
Elanco Animal Health Incorporated Aqua Business
Business Acquisition [Line Items]
Inventories		$ 74
Property, plant and equipment		67
Other assets and liabilities, net		24
Total identifiable net assets		796
Goodwill		505
Consideration transferred		$ 1,301
Discount rate		8.50%
Elanco Animal Health Incorporated Aqua Business | Product Rights
Business Acquisition [Line Items]
Identifiable intangible assets		$ 340
Elanco Animal Health Incorporated Aqua Business | Other Product Rights
Business Acquisition [Line Items]
Identifiable intangible assets		$ 291
Identifiable intangible assets, useful life		15 years

Collaborative Arrangements - As

Collaborative Arrangements - AstraZeneca PLC - Narrative (Details) - Lynparza - USD ($)	9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2022
Licenses and Other
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Finite-lived intangible assets	$ 1,300,000,000
AstraZeneca | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Probable contingent payments			$ 600,000,000
Liabilities			$ 600,000,000
Eligible future contingent sales-based milestone payments (up to)	2,100,000,000
Regulatory milestone payments	245,000,000	$ 105,000,000
Eligible future contingent regulatory milestone payments (up to)	$ 0

Collaborative Arrangements - _2

Collaborative Arrangements - AstraZeneca PLC (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Cost of sales	$ 4,080	$ 4,264	$ 11,365	$ 12,214
Selling, general and administrative	2,731	2,519	7,952	7,700
Research and development	5,862	3,307	13,354	20,904
Other current assets	40,361		40,361		$ 32,168
Accrued and other current liabilities	16,539		16,539		15,766
AstraZeneca | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue from collaborative arrangement	376	325	1,061	958
Cost of sales	82	82	245	230
Selling, general and administrative	39	44	121	143
Research and development	19	23	57	65
Other current assets	375		375		341
Accrued and other current liabilities	615		615		256
Other noncurrent liabilities	0		0		$ 600
AstraZeneca | Alliance revenue - Lynparza | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue from collaborative arrangement	337	299	947	884
AstraZeneca | Alliance revenue - Koselugo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue from collaborative arrangement	$ 39	$ 26	$ 114	$ 74

Collaborative Arrangements - Ei

Collaborative Arrangements - Eisai Co., Ltd. - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Mar. 31, 2023	Sep. 30, 2023	Sep. 30, 2024
Alliance revenue - Lenvima | Licenses and Other
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Finite-lived intangible assets				$ 502,000,000
Eisai
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Amortization of intangible assets	$ 81,000,000		$ 154,000,000
Eisai | Alliance revenue - Lenvima | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Probable contingent payments	125,000,000	$ 125,000,000
Liabilities	$ 250,000,000		$ 250,000,000
Eligible future contingent sales-based milestone payments (up to)				2,300,000,000
Eligible future contingent regulatory milestone payments (up to)				0
Bayer AG | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Eligible future contingent sales-based milestone payments (up to)				$ 0

Collaborative Arrangements - _3

Collaborative Arrangements - Eisai Co., Ltd. (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Cost of sales	$ 4,080	$ 4,264	$ 11,365	$ 12,214
Selling, general and administrative	2,731	2,519	7,952	7,700
Research and development	5,862	3,307	13,354	20,904
Other current assets	40,361		40,361		$ 32,168
Accrued and other current liabilities	16,539		16,539		15,766
Eisai
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Amortization of intangible assets		81		154
Eisai | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue from collaborative arrangement	251	260	755	734
Cost of sales	60	137	181	320
Selling, general and administrative	40	46	120	145
Research and development	4	$ 5	18	$ 61
Other current assets	252		252		226
Accrued and other current liabilities	$ 0		$ 0		$ 125

Collaborative Arrangements - Ba

Collaborative Arrangements - Bayer AG (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Sales	$ 16,657,000,000	$ 15,962,000,000	$ 48,544,000,000	$ 45,485,000,000
Cost of sales	4,080,000,000	4,264,000,000	11,365,000,000	12,214,000,000
Selling, general and administrative	2,731,000,000	2,519,000,000	7,952,000,000	7,700,000,000
Research and development	5,862,000,000	3,307,000,000	13,354,000,000	20,904,000,000
Other current assets	40,361,000,000		40,361,000,000		$ 32,168,000,000
Accrued and other current liabilities	16,539,000,000		16,539,000,000		15,766,000,000
Bayer AG | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Eligible future contingent sales-based milestone payments (up to)	0		0
Revenue from collaborative arrangement	102,000,000	92,000,000	306,000,000	259,000,000
Sales	185,000,000	165,000,000	545,000,000	472,000,000
Cost of sales	59,000,000	53,000,000	182,000,000	165,000,000
Selling, general and administrative	29,000,000	33,000,000	88,000,000	100,000,000
Research and development	27,000,000	26,000,000	82,000,000	76,000,000
Other current assets	166,000,000		166,000,000		156,000,000
Accrued and other current liabilities	82,000,000		82,000,000		$ 80,000,000
Adempas | Bayer AG | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Sales	72,000,000	65,000,000	214,000,000	189,000,000
Adempas | Licenses and Other
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Finite-lived intangible assets	431,000,000		431,000,000
Verquvo | Bayer AG | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Sales	11,000,000	$ 8,000,000	25,000,000	$ 24,000,000
Verquvo | Licenses and Other
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Finite-lived intangible assets	$ 47,000,000		$ 47,000,000

Collaborative Arrangements - Ri

Collaborative Arrangements - Ridgeback Biotherapeutics LP (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Sales	$ 16,657	$ 15,962	$ 48,544	$ 45,485
Cost of sales	4,080	4,264	11,365	12,214
Selling, general and administrative	2,731	2,519	7,952	7,700
Accrued and other current liabilities	16,539		16,539		$ 15,766
Ridgeback Biotherapeutics LP | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Cost of sales	204	348	491	762
Selling, general and administrative	11	21	43	72
Research and development	5	8	7	33
Accrued and other current liabilities	176		176		$ 113
Ridgeback Biotherapeutics LP | Lagevrio | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Sales	$ 383	$ 640	$ 843	$ 1,236

Collaborative Arrangements - Da

Collaborative Arrangements - Daiicho Sankyo - Narrative (Details) $ in Millions	1 Months Ended	3 Months Ended			9 Months Ended
	Aug. 31, 2024 USD ($)	Sep. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Oct. 31, 2023 USD ($) candidate
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development		$ 5,862		$ 3,307	$ 13,354	$ 20,904
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of antibody drug conjugates obtained right and obligations | candidate							3
Aggregate upfront payments due upon execution in collaborative arrangement							$ 4,000
Refundable upfront payments in collaborative arrangement							1,000
Maximum aggregate contingent milestone payments, per product, in collaborative arrangement							$ 5,500
Research and development		$ 94	$ 5,500	$ 0	$ 227	$ 0
Sales based royalty percentage							5%
Upfront cash payment	$ 170
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Ifinatamab Deruxtecan
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Refundable upfront payments in collaborative arrangement							$ 500
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Patritumab Deruxtecan
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Refundable upfront payments in collaborative arrangement							500
Aggregate upfront payments due upon lapse of time in collaborative arrangement							750
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Raludotatug Deruxtecan
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Aggregate upfront payments due upon lapse of time in collaborative arrangement							$ 750
Liable contracted portion of research and development expenses to incur costs for in collaborative arrangement, percentage							75%
Liable contracted portion of research and development expenses to incur costs for in collaborative arrangement							$ 2,000
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Patritumab Deruxtecan And Raludotatug Deruxtecan
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Aggregate upfront payments due upon lapse of time in collaborative arrangement			$ 1,500

Collaborative Arrangements - _4

Collaborative Arrangements - Daiicho Sankyo (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Selling, general and administrative	$ 2,731		$ 2,519	$ 7,952	$ 7,700
Research and development	5,862		3,307	13,354	20,904
Accrued and other current liabilities	16,539	$ 15,766		16,539
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Selling, general and administrative	5		0	21	0
Research and development	94	5,500	$ 0	227	$ 0
Accrued and other current liabilities	811	800		811
Other noncurrent liabilities	$ 750	$ 750		$ 750

Collaborative Arrangements - Mo

Collaborative Arrangements - Moderna, Inc. - Narrative (Details) $ in Millions	Sep. 30, 2024 USD ($)
Moderna, Inc. | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Capitalization of shared costs	$ 172

Collaborative Arrangements - _5

Collaborative Arrangements - Moderna, Inc. (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Selling, general and administrative	$ 2,731	$ 2,519	$ 7,952	$ 7,700
Research and development	5,862	3,307	13,354	20,904
Accrued and other current liabilities	16,539		16,539		$ 15,766
Moderna, Inc. | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Selling, general and administrative	5	2	11	3
Research and development	93	$ 66	255	$ 153
Accrued and other current liabilities	$ 68		$ 68		$ 63

Collaborative Arrangements - Br

Collaborative Arrangements - Bristol Meyers Squibb Company - Narrative (Details) - Bristol Myers Squibb Company - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Licensing Agreements
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Royalty rate, deduction			0.50
Licensing Agreements | Alliance Revenue - Reblozyl
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Eligible future contingent sales-based milestone payments (up to)	$ 80		$ 80
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue from collaborative arrangement	$ 100	$ 52	$ 261	$ 142
Minimum | Licensing Agreements
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Royalty rate			20%
Maximum | Licensing Agreements
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Royalty rate			24%

Restructuring - Narrative (Deta

Restructuring - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs			$ 701
Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Expected restructuring and related cost	$ 4,000		4,000
Estimate of cumulative pre tax costs that will be noncash	60%
Total pretax restructuring costs	$ 279		701
Cumulative costs since program inception	$ 892		$ 892
Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		$ 199		$ 532

Restructuring - Charges Activit

Restructuring - Charges Activities by Type of Cost (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs			$ 701
Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	$ 279		701
Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		$ 199		$ 532
Accelerated Depreciation
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs			171
Accelerated Depreciation | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	40		171
Accelerated Depreciation | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		36		79
Separation Costs
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs			122
Separation Costs | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	11		122
Separation Costs | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		95		246
Other Exit Costs
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs			408
Other Exit Costs | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	228		408
Other Exit Costs | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		68		207
Cost of sales | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	192		374
Cost of sales | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		33		94
Cost of sales | Accelerated Depreciation | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	40		171
Cost of sales | Accelerated Depreciation | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		31		74
Cost of sales | Separation Costs | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	0		0
Cost of sales | Separation Costs | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		0		0
Cost of sales | Other Exit Costs | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	152		203
Cost of sales | Other Exit Costs | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		2		20
Selling, general and administrative | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	31		67
Selling, general and administrative | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		40		93
Selling, general and administrative | Accelerated Depreciation | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	0		0
Selling, general and administrative | Accelerated Depreciation | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		5		5
Selling, general and administrative | Separation Costs | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	0		0
Selling, general and administrative | Separation Costs | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		0		0
Selling, general and administrative | Other Exit Costs | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	31		67
Selling, general and administrative | Other Exit Costs | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		35		88
Research and development | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	0		2
Research and development | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		0		1
Research and development | Accelerated Depreciation | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	0		0
Research and development | Accelerated Depreciation | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		0		0
Research and development | Separation Costs | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	0		0
Research and development | Separation Costs | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		0		0
Research and development | Other Exit Costs | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	0		2
Research and development | Other Exit Costs | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		0		1
Restructuring costs | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	56		258
Restructuring costs | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		126		344
Restructuring costs | Accelerated Depreciation | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	0		0
Restructuring costs | Accelerated Depreciation | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		0		0
Restructuring costs | Separation Costs | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	11		122
Restructuring costs | Separation Costs | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		95		246
Restructuring costs | Other Exit Costs | Restructuring Program, 2024
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs	$ 45		$ 136
Restructuring costs | Other Exit Costs | Restructuring Program, 2019
Restructuring Cost and Reserve [Line Items]
Total pretax restructuring costs		$ 31		$ 98

Restructuring - Activities by P

Restructuring - Activities by Program (Details) $ in Millions	9 Months Ended
	Sep. 30, 2024 USD ($)
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	$ 712
Expenses	701
(Payments) receipts, net	(299)
Non-cash activity	(463)
Restructuring reserve, ending balance	651
Accelerated Depreciation
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	0
Expenses	171
(Payments) receipts, net	0
Non-cash activity	(171)
Restructuring reserve, ending balance	0
Separation Costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	681
Expenses	122
(Payments) receipts, net	(177)
Non-cash activity	0
Restructuring reserve, ending balance	626
Other Exit Costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	31
Expenses	408
(Payments) receipts, net	(122)
Non-cash activity	(292)
Restructuring reserve, ending balance	$ 25

Financial Instruments - Narrati

Financial Instruments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Derivative [Line Items]
Pretax net unrealized gain on derivatives maturing within the next 12 months estimated to be reclassified from AOCI to sales	$ (161)		$ (161)
Equity investments without readily determinable fair values	848	$ 863	848	$ 863
Unrealized gains recognized on investments in equity securities without readily determinable fair value			12	7
Unrealized losses recognized on investments in equity securities without readily determinable fair values			25	24
Cumulative unrealized gains on investments	302		302
Cumulative unrealized losses on investments	89		89
Loss (income) from investments in equity securities, net	31	33	(169)	(240)
Payments			(148)	(117)
Fair value of loans payable and long-term debt, including current portion	35,200		35,200		$ 32,000
Debt, carrying amount	38,100		38,100		35,100
Factored accounts receivable			3,100		3,000
Cash collateral received from counterparties	0		0		3
Lyfnua
Derivative [Line Items]
Payments			(22)
Sanofi Pasteur
Derivative [Line Items]
Payments			(126)
Equity Funds
Derivative [Line Items]
Equity securities held through ownership interest in investments funds	328	467	328	467
Loss (income) from investments in equity securities, net	(21)	$ 93	(26)	$ 66
Accounts Receivable Factoring Collections
Derivative [Line Items]
Restricted cash	42		42		44
Level 2
Derivative [Line Items]
Cash equivalents	$ 13,600		$ 13,600		$ 6,000
Maximum | Derivatives Designated as Hedging Instruments
Derivative [Line Items]
Maximum average period of maturities of contracts in years (less than)			2 years
Maximum | Derivatives Not Designated as Hedging Instruments
Derivative [Line Items]
Maximum average period of maturities of contracts in years (less than)			6 months

Financial Instruments - Effect

Financial Instruments - Effect of Net Investment Hedges (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Pretax (Gain) Loss Recognized in Other Comprehensive Income	$ 1	$ (1)	$ 4	$ 0
Foreign exchange contracts | Other (income) expense, net
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Pretax (Gain) Loss Recognized in Other (income) expense, net for Amounts Excluded from Effectiveness Testing	0	0	2	(1)
Euro-denominated notes
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Pretax (Gain) Loss Recognized in Other Comprehensive Income	169	(100)	73	(26)
Euro-denominated notes | Other (income) expense, net
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Pretax (Gain) Loss Recognized in Other (income) expense, net for Amounts Excluded from Effectiveness Testing	$ 0	$ 0	$ 0	$ 0

Financial Instruments - Summary

Financial Instruments - Summary of Interest Rate Swaps Held (Details)	Sep. 30, 2024 USD ($) interest_rate_swap	May 31, 2024 EUR (€)	Dec. 31, 2023 USD ($)
Derivative [Line Items]
U.S dollar notional amount	$ 35,314,000,000		$ 30,551,000,000
Senior Notes
Derivative [Line Items]
Par Value of Debt | €		€ 3,400,000,000
4.50% note due 2033 | Senior Notes
Derivative [Line Items]
Stated interest rate	4.50%
Interest rate swap contracts
Derivative [Line Items]
Number of Interest Rate Swaps Held | interest_rate_swap	6
Interest rate swap contracts | 4.50% note due 2033
Derivative [Line Items]
Par Value of Debt	$ 1,500,000,000
Number of Interest Rate Swaps Held | interest_rate_swap	6
U.S dollar notional amount	$ 1,500,000,000

Financial Instruments - Amounts

Financial Instruments - Amounts Recorded on Balance Sheet Related to Fair Value Hedges (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Hedged Liability, Statement of Financial Position [Extensible Enumeration]	Long-Term Debt	Long-Term Debt
Carrying Amount of Hedged Liabilities	$ 1,589	$ 1,056
Cumulative Amount of Fair Value Hedging Adjustment Increase Included in the Carrying Amount	$ 98	$ 56

Financial Instruments - Fair Va

Financial Instruments - Fair Value of Derivatives Segregated between those Derivatives that are Designated as Hedging Instruments and those that are Not Designated as Hedging Instruments (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	$ 340	$ 342
Fair value of derivative, liability	298	239
U.S dollar notional amount	35,314	30,551
Derivatives Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	157	189
Fair value of derivative, liability	119	77
U.S dollar notional amount	13,381	12,754
Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	183	153
Fair value of derivative, liability	179	162
U.S dollar notional amount	$ 21,933	$ 17,797
Interest rate swap contracts | Derivatives Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets	Other Assets
Fair value of derivative, asset	$ 99	$ 57
Derivative asset, notional amount	$ 1,500	$ 1,000
Foreign exchange contracts | Derivatives Designated as Hedging Instruments | Other current assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other current assets	Other current assets
Fair value of derivative, asset	$ 30	$ 106
Derivative asset, notional amount	$ 4,635	$ 6,138
Foreign exchange contracts | Derivatives Designated as Hedging Instruments | Other Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets	Other Assets
Fair value of derivative, asset	$ 28	$ 26
Derivative asset, notional amount	$ 2,170	$ 1,929
Foreign exchange contracts | Derivatives Designated as Hedging Instruments | Accrued and other current liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Accrued and other current liabilities	Accrued and other current liabilities
Fair value of derivative, liability	$ 118	$ 76
Derivative liability, notional amount	$ 5,022	$ 3,680
Foreign exchange contracts | Derivatives Designated as Hedging Instruments | Other Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other Noncurrent Liabilities	Other Noncurrent Liabilities
Fair value of derivative, liability	$ 1	$ 1
Derivative liability, notional amount	$ 54	$ 7
Foreign exchange contracts | Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other current assets	Other current assets
Fair value of derivative, asset	$ 183	$ 153
Derivative asset, notional amount	$ 10,298	$ 9,693
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Accrued and other current liabilities	Accrued and other current liabilities
Fair value of derivative, liability	$ 179	$ 162
Derivative liability, notional amount	$ 11,635	$ 8,104

Financial Instruments - Informa

Financial Instruments - Information on Derivative Positions Subject to Master Netting Arrangements as if they were Presented on a Net Basis (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Gross amounts recognized in the consolidated balance sheet, asset	$ 340	$ 342
Gross amount subject to offset in master netting arrangements not offset in the condensed balance sheet, asset	(225)	(215)
Cash collateral received, asset	0	(3)
Net amounts, asset	115	124
Gross amounts recognized in the consolidated balance sheet, liability	298	239
Gross amount subject to offset in master netting arrangements not offset in the condensed balance sheet, liability	(225)	(215)
Cash collateral received, liability	0	0
Net amounts, liability	$ 73	$ 24

Financial Instruments - Locatio

Financial Instruments - Location and Amount of Pretax (Gains) Losses of Derivatives (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Derivative Instruments, Gain (Loss) [Line Items]
Sales	$ 16,657	$ 15,962	$ 48,544	$ 45,485
Other (income) expense, net	(162)	126	(151)	388
Other comprehensive income (loss)	(10)	(16)	$ (210)	$ (148)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Other (income) expense, net	Other (income) expense, net
Interest rate swap contracts | Other (income) expense, net
Derivative Instruments, Gain (Loss) [Line Items]
Hedged items	68	(7)	$ 42	$ (7)
Derivatives designated as hedging instruments	(69)	8	(43)	8
Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in OCI on derivatives	(325)	247	22	375
Increase in Sales as a result of AOCL reclassifications	(48)	(45)	(146)	(170)
Foreign exchange contracts | Reclassification out of Accumulated Other Comprehensive Income | Accumulated Gain (Loss), Cash Flow Hedge, Including Noncontrolling Interest
Derivative Instruments, Gain (Loss) [Line Items]
Sales	$ 48	$ 45	146	170
Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in OCI on derivatives			(1)	13
Amount of gain recognized in Other (income) expense, net on derivatives			$ (1)	$ (1)

Financial Instruments - Income

Financial Instruments - Income Statement Effects on Derivatives Not Designated as Hedging Instruments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Currency Swap | Other (income) expense, net
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Derivative Pretax (Gain) Loss Recognized in Income	$ (139)	$ 60	$ (65)	$ 32
Foreign Exchange Future | Sales
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Derivative Pretax (Gain) Loss Recognized in Income	$ 10	$ 0	$ (10)	$ (3)

Financial Instruments - Infor_2

Financial Instruments - Information on Available-for-sale Investments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	$ 81		$ 81		$ 337
Debt securities, unrealized gains	0		0		0
Debt securities, unrealized losses	0		0		0
Debt securities, fair value	81		81		337
Publicly traded equity securities, fair value	984		984		764
Total debt and publicly traded equity securities, fair value	1,065		1,065		1,101
Unrealized net losses (gains)	42	$ 61	(82)	$ 327
U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	81		81		72
Debt securities, unrealized gains	0		0		0
Debt securities, unrealized losses	0		0		0
Debt securities, fair value	81		81		72
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	0		0		252
Debt securities, unrealized gains	0		0		0
Debt securities, unrealized losses	0		0		0
Debt securities, fair value	0		0		252
Corporate notes and bonds
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	0		0		13
Debt securities, unrealized gains	0		0		0
Debt securities, unrealized losses	0		0		0
Debt securities, fair value	$ 0		$ 0		$ 13

Financial Instruments - Financi

Financial Instruments - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022
Assets
Investments	$ 81	$ 337
Publicly traded equity securities	984	764
Other Assets	14,443	11,996
Fair value of derivative, asset	340	342
Liabilities
Contingent consideration	208	354	$ 345	$ 456
Fair value of derivative, liability	298	239
Cumulative unrealized gains on investments	302
Cumulative unrealized losses on investments	89
Commercial paper
Assets
Investments	0	252
U.S. government and agency securities
Assets
Investments	81	72
Corporate notes and bonds
Assets
Investments	0	13
Fair Value, Measurements, Recurring
Assets
Investments	575	504
Other Assets	490	597
Fair value of derivative, asset	340	342
Total assets	1,405	1,443
Liabilities
Contingent consideration	208	354
Fair value of derivative, liability	298	239
Total liabilities	506	593
Fair Value, Measurements, Recurring | Foreign exchange contracts
Assets
Fair value of derivative, asset	180	202
Liabilities
Fair value of derivative, liability	291	239
Fair Value, Measurements, Recurring | Interest rate swap contracts
Assets
Fair value of derivative, asset	99	57
Fair Value, Measurements, Recurring | Currency options
Assets
Fair value of derivative, asset	61	83
Liabilities
Fair value of derivative, liability	7	0
Fair Value, Measurements, Recurring | Level 1
Assets
Investments	575	252
Other Assets	490	597
Fair value of derivative, asset	0	0
Total assets	1,065	849
Liabilities
Contingent consideration	0	0
Fair value of derivative, liability	0	0
Total liabilities	0	0
Fair Value, Measurements, Recurring | Level 1 | Foreign exchange contracts
Assets
Fair value of derivative, asset	0	0
Liabilities
Fair value of derivative, liability	0	0
Fair Value, Measurements, Recurring | Level 1 | Interest rate swap contracts
Assets
Fair value of derivative, asset	0	0
Fair Value, Measurements, Recurring | Level 1 | Currency options
Assets
Fair value of derivative, asset	0	0
Liabilities
Fair value of derivative, liability	0	0
Fair Value, Measurements, Recurring | Level 2
Assets
Investments	0	252
Other Assets	0	0
Fair value of derivative, asset	340	342
Total assets	340	594
Liabilities
Contingent consideration	0	0
Fair value of derivative, liability	298	239
Total liabilities	298	239
Fair Value, Measurements, Recurring | Level 2 | Foreign exchange contracts
Assets
Fair value of derivative, asset	180	202
Liabilities
Fair value of derivative, liability	291	239
Fair Value, Measurements, Recurring | Level 2 | Interest rate swap contracts
Assets
Fair value of derivative, asset	99	57
Fair Value, Measurements, Recurring | Level 2 | Currency options
Assets
Fair value of derivative, asset	61	83
Liabilities
Fair value of derivative, liability	7	0
Fair Value, Measurements, Recurring | Level 3
Assets
Investments	0	0
Other Assets	0	0
Fair value of derivative, asset	0	0
Total assets	0	0
Liabilities
Contingent consideration	208	354
Fair value of derivative, liability	0	0
Total liabilities	208	354
Fair Value, Measurements, Recurring | Level 3 | Foreign exchange contracts
Assets
Fair value of derivative, asset	0	0
Liabilities
Fair value of derivative, liability	0	0
Fair Value, Measurements, Recurring | Level 3 | Interest rate swap contracts
Assets
Fair value of derivative, asset	0	0
Fair Value, Measurements, Recurring | Level 3 | Currency options
Assets
Fair value of derivative, asset	0	0
Liabilities
Fair value of derivative, liability	0	0
Fair Value, Measurements, Recurring | Commercial paper
Assets
Investments	0	252
Fair Value, Measurements, Recurring | Commercial paper | Level 1
Assets
Investments	0	0
Fair Value, Measurements, Recurring | Commercial paper | Level 2
Assets
Investments	0	252
Fair Value, Measurements, Recurring | Commercial paper | Level 3
Assets
Investments	0	0
Fair Value, Measurements, Recurring | U.S. government and agency securities
Assets
Debt securities, available-for-sale, noncurrent	81	72
Fair Value, Measurements, Recurring | U.S. government and agency securities | Level 1
Assets
Debt securities, available-for-sale, noncurrent	81	72
Fair Value, Measurements, Recurring | U.S. government and agency securities | Level 2
Assets
Debt securities, available-for-sale, noncurrent	0	0
Fair Value, Measurements, Recurring | U.S. government and agency securities | Level 3
Assets
Debt securities, available-for-sale, noncurrent	0	0
Fair Value, Measurements, Recurring | Corporate notes and bonds
Assets
Debt securities, available-for-sale, noncurrent	0	13
Fair Value, Measurements, Recurring | Corporate notes and bonds | Level 1
Assets
Debt securities, available-for-sale, noncurrent	0	13
Fair Value, Measurements, Recurring | Corporate notes and bonds | Level 2
Assets
Debt securities, available-for-sale, noncurrent	0	0
Fair Value, Measurements, Recurring | Corporate notes and bonds | Level 3
Assets
Debt securities, available-for-sale, noncurrent	0	0
Fair Value, Measurements, Recurring | Publicly traded equity securities
Assets
Publicly traded equity securities	575	252
Publicly traded equity securities	409	512
Fair Value, Measurements, Recurring | Publicly traded equity securities | Level 1
Assets
Publicly traded equity securities	575	252
Publicly traded equity securities	409	512
Fair Value, Measurements, Recurring | Publicly traded equity securities | Level 2
Assets
Publicly traded equity securities	0	0
Publicly traded equity securities	0	0
Fair Value, Measurements, Recurring | Publicly traded equity securities | Level 3
Assets
Publicly traded equity securities	0	0
Publicly traded equity securities	$ 0	$ 0

Financial Instruments - Infor_3

Financial Instruments - Information About Changes in Liabilities for Contingent Consideration (Details) $ in Millions	9 Months Ended
	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	$ 354	$ 456
Changes in estimated fair value	2	6
Payments	(148)	(117)
Fair value, ending balance	208	$ 345
Current liability	163
Sanofi Pasteur
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Payments	(126)
Current liability	$ 136
Contingent consideration, measurement input, discount rate	0.115

Inventories - Schedule of Inven

Inventories - Schedule of Inventories (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Inventory Disclosure [Abstract]
Finished goods	$ 1,939	$ 1,954
Raw materials and work in process	8,780	8,037
Supplies	282	277
Total	11,001	10,268
Decrease to LIFO cost	(762)	(562)
Total current and noncurrent inventories	10,239	9,706
Recognized as:
Inventories	6,244	6,358
Other Assets	$ 3,995	$ 3,348

Inventories - Narrative (Detail

Inventories - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Inventory [Line Items]
Inventories classified in Other assets	$ 3,995	$ 3,348
Inventories Not Expected to be Sold Within One Year
Inventory [Line Items]
Inventories classified in Other assets	3,700	2,600
Inventories Produced in Preparation for Product Launches
Inventory [Line Items]
Inventories classified in Other assets	$ 334	$ 790

Long-Term Debt (Details)

Long-Term Debt (Details) - Senior Notes	May 31, 2024 EUR (€)
Debt Instrument [Line Items]
Face amount of debt	€ 3,400,000,000
3.25% Notes due 2032
Debt Instrument [Line Items]
Face amount of debt	€ 850,000,000
Stated interest rate	3.25%
3.50% Notes due 2037
Debt Instrument [Line Items]
Face amount of debt	€ 850,000,000
Stated interest rate	3.50%
3.70% Notes due 2044
Debt Instrument [Line Items]
Face amount of debt	€ 850,000,000
Stated interest rate	3.70%
3.75% Notes due 2054
Debt Instrument [Line Items]
Face amount of debt	€ 850,000,000
Stated interest rate	3.75%

Contingencies (Details)

Contingencies (Details) $ in Millions			1 Months Ended					9 Months Ended
	Mar. 15, 2024	Apr. 13, 2023 patent	Feb. 29, 2024 patent	Jul. 31, 2023 motion	Jun. 30, 2023	Feb. 28, 2023 patent	Jun. 30, 2012 employee	Sep. 30, 2024 USD ($) case company lawsuit	Dec. 31, 2023 USD ($)
Legal Defense Costs
Loss Contingencies [Line Items]
Legal defense costs reserve | $								$ 210	$ 210
U.S. | Pending Litigation | Qui Tam
Loss Contingencies [Line Items]
Loss contingency, pending claims | lawsuit								2
U.S. | Settled Litigation | Qui Tam
Loss Contingencies [Line Items]
Loss contingency, number of plaintiffs | employee							2
Motion for summary judgement, motions granted | motion				2
Dr. Scholl's | U.S. | Pending Litigation
Loss Contingencies [Line Items]
Loss contingency, pending claims | case								330
Gardasil/Gardasil 9 | Non-US | Pending Litigation
Loss Contingencies [Line Items]
Loss contingency, pending claims | case								15
Gardasil/Gardasil 9 | U.S. | Pending Litigation
Loss Contingencies [Line Items]
Loss contingency, pending claims | case								210
Bridion | Patents
Loss Contingencies [Line Items]
Loss contingency, claims settled | company								5
Bridion | Pending Litigation | Patents
Loss Contingencies [Line Items]
Loss contingency, pending claims | company								2
Postponement period resulting from litigation	30 months
Bridion | Settled Litigation | Patents
Loss Contingencies [Line Items]
Patent extension, term					5 years
Keytruda | Pending Litigation | Patents
Loss Contingencies [Line Items]
Loss contingency, number of patents allegedly infringed | patent		9
Lynparza | Pending Litigation | Patents
Loss Contingencies [Line Items]
Loss contingency, number of patents allegedly infringed | patent			1			1
Januvia/Janumet
Loss Contingencies [Line Items]
Loss contingency, claims settled | company								26

Equity (Details)

Equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, beginning balance (in shares)			3,577,103,522
Treasury stock, beginning balance (in shares)			1,045,470,249
Equity, beginning balance	$ 43,648	$ 38,742	$ 37,635	$ 46,058
Net income attributable to Merck & Co., Inc.	3,157	4,745	13,374	1,591
Other comprehensive income (loss), net of taxes	(10)	(16)	(210)	(148)
Cash dividends declared on common stock	(1,960)	(1,861)	(5,885)	(5,590)
Treasury stock shares purchased	(444)	(466)	(817)	(953)
Share-based compensation plans and other	177	151	460	355
Net income attributable to noncontrolling interests	4	5	15	12
Distributions attributable to noncontrolling interests	$ (12)		$ (12)	(25)
Common stock, ending balance (in shares)	3,577,103,522		3,577,103,522
Treasury stock, ending balance (in shares)	1,045,073,377		1,045,073,377
Equity, ending balance	$ 44,560	$ 41,300	$ 44,560	$ 41,300
Cash dividends declared on common stock (in dollars per share)	$ 0.77	$ 0.73	$ 2.31	$ 2.19
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, beginning balance (in shares)	3,577,000,000	3,577,000,000	3,577,000,000	3,577,000,000
Equity, beginning balance	$ 1,788	$ 1,788	$ 1,788	$ 1,788
Common stock, ending balance (in shares)	3,577,000,000	3,577,000,000	3,577,000,000	3,577,000,000
Equity, ending balance	$ 1,788	$ 1,788	$ 1,788	$ 1,788
Other Paid-In Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity, beginning balance	44,362	44,219	44,509	44,379
Share-based compensation plans and other	168	139	21	(21)
Equity, ending balance	44,530	44,358	44,530	44,358
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity, beginning balance	60,187	54,198	53,895	61,081
Net income attributable to Merck & Co., Inc.	3,157	4,745	13,374	1,591
Cash dividends declared on common stock	(1,960)	(1,861)	(5,885)	(5,590)
Equity, ending balance	61,384	57,082	61,384	57,082
Accumulated Other Comprehensive Loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity, beginning balance	(5,361)	(4,900)	(5,161)	(4,768)
Other comprehensive income (loss), net of taxes	(10)	(16)	(210)	(148)
Equity, ending balance	$ (5,371)	$ (4,916)	$ (5,371)	$ (4,916)
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury stock, beginning balance (in shares)	1,041,000,000	1,038,000,000	1,045,000,000	1,039,000,000
Equity, beginning balance	$ (57,394)	$ (56,612)	$ (57,450)	$ (56,489)
Treasury stock shares purchased (in shares)	4,000,000	4,000,000	7,000,000	9,000,000
Treasury stock shares purchased	$ (444)	$ (466)	$ (817)	$ (953)
Share-based compensation plans and other (in shares)	0		(7,000,000)	(6,000,000)
Share-based compensation plans and other	$ 9	$ 12	$ 438	$ 376
Treasury stock, ending balance (in shares)	1,045,000,000	1,042,000,000	1,045,000,000	1,042,000,000
Equity, ending balance	$ (57,829)	$ (57,066)	$ (57,829)	$ (57,066)
Non- controlling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity, beginning balance	66	49	54	67
Share-based compensation plans and other			1
Net income attributable to noncontrolling interests	4	5	15	12
Distributions attributable to noncontrolling interests	(12)		(12)	(25)
Equity, ending balance	$ 58	$ 54	$ 58	$ 54

Pension and Other Postretirem_3

Pension and Other Postretirement Benefit Plans - Net Benefit Costs (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Other Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 7	$ 8	$ 23	$ 24
Interest cost	14	16	42	47
Expected return on plan assets	(20)	(16)	(60)	(48)
Amortization of unrecognized prior service (credit) cost	(11)	(12)	(32)	(37)
Net loss (gain) amortization	(14)	(11)	(38)	(31)
Curtailments	0	0	0	(1)
Net periodic benefit cost	(24)	(15)	(65)	(46)
U.S. | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	100	88	273	239
Interest cost	134	130	403	396
Expected return on plan assets	(206)	(182)	(621)	(553)
Amortization of unrecognized prior service (credit) cost	0	0	0	(1)
Net loss (gain) amortization	12	0	30	0
Termination benefits	1	1	5	2
Curtailments	0	0	0	5
Settlements	0	0	0	26
Net periodic benefit cost	41	37	90	114
International | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	60	48	182	148
Interest cost	74	76	220	225
Expected return on plan assets	(139)	(131)	(416)	(390)
Amortization of unrecognized prior service (credit) cost	(3)	(6)	(10)	5
Net loss (gain) amortization	1	(1)	4	(2)
Termination benefits	0	0	0	0
Curtailments	0	0	0	0
Settlements	0	0	0	0
Net periodic benefit cost	$ (7)	$ (14)	$ (20)	$ (14)

Pension and Other Postretirem_4

Pension and Other Postretirement Benefit Plans - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2023
Retirement Benefits [Abstract]
Increase to pension liabilities due to remeasurement	$ 34	$ (13)

Other (Income) Expense, Net - S

Other (Income) Expense, Net - Schedule of Other (Income) Expense, Net (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Other Income and Expenses [Abstract]
Interest income	$ (127)	$ (73)	$ (269)	$ (295)
Interest expense	330	317	943	836
Exchange losses	33	85	177	208
Loss (income) from investments in equity securities, net	31	33	(169)	(240)
Net periodic defined benefit plan (credit) cost other than service cost	(157)	(138)	(476)	(364)
Other, net	(272)	(98)	(357)	243
Other (income) expense, net	$ (162)	$ 126	$ (151)	$ 388

Other (Income) Expense, Net - N

Other (Income) Expense, Net - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Loss Contingencies [Line Items]
Interest paid	$ 822	$ 678
Zetia antitrust litigation
Loss Contingencies [Line Items]
Loss related to litigation settlement		$ 572.5

Income Taxes (Details)

Income Taxes (Details) - USD ($)	3 Months Ended			9 Months Ended
	Dec. 31, 2024	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Effective income tax rate		22.70%	15.50%	15.10%	59.30%
Income tax rate, unfavorable discrete impact		7.20%		2.10%	44%
Income tax rate, favorable impact				1.60%
Tax benefit resulting from a reduction in reserves for unrecognized tax benefits				$ 259,000,000
Tax benefit resulting from acquisition charge					$ 0
Forecast
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Tax benefit resulting from a reduction in reserves for unrecognized tax benefits	$ 270,000,000

Earnings Per Share - Calculatio

Earnings Per Share - Calculations of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Earnings Per Share [Abstract]
Net Income (Loss) Attributable to Merck & Co., Inc., basic	$ 3,157	$ 4,745	$ 13,374	$ 1,591
Net Income (Loss) Attributable to Merck & Co., Inc., diluted	$ 3,157	$ 4,745	$ 13,374	$ 1,591
Average common shares outstanding (in shares)	2,534	2,537	2,534	2,538
Common shares issuable (in shares)	7	9	9	11
Average common shares outstanding assuming dilution (in shares)	2,541	2,546	2,543	2,549
Basic Earnings per Common Share Attributable to Merck & Co., Inc. Common Shareholders (in dollars per share)	$ 1.25	$ 1.87	$ 5.28	$ 0.63
Earnings per Common Share Assuming Dilution Attributable to Merck & Co., Inc. Common Shareholders (in dollars per share)	$ 1.24	$ 1.86	$ 5.26	$ 0.62

Earnings Per Share - Narrative

Earnings Per Share - Narrative (Details) - shares shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Earnings Per Share [Abstract]
Antidilutive shares (in shares)	7	6	6	5

Other Comprehensive Income (L_3

Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Equity, beginning balance	$ 43,648	$ 38,742	$ 37,635	$ 46,058
Other comprehensive income (loss), net of taxes	(10)	(16)	(210)	(148)
Equity, ending balance	44,560	41,300	44,560	41,300
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Equity, beginning balance	(5,361)	(4,900)	(5,161)	(4,768)
Other comprehensive income (loss) before reclassification adjustments, pretax	(46)	24	(75)	63
Tax	85	18	(10)	(48)
Other comprehensive income (loss) before reclassification adjustments, net of taxes	39	42	(85)	15
Reclassification adjustments, pretax	(63)	(72)	(171)	(206)
Tax	14	14	46	43
Reclassification adjustments, net of taxes	(49)	(58)	(125)	(163)
Other comprehensive income (loss), net of taxes	(10)	(16)	(210)	(148)
Equity, ending balance	(5,371)	(4,916)	(5,371)	(4,916)
Derivatives
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Equity, beginning balance	173	85	(24)	73
Other comprehensive income (loss) before reclassification adjustments, pretax	(325)	247	22	375
Tax	68	(52)	(5)	(79)
Other comprehensive income (loss) before reclassification adjustments, net of taxes	(257)	195	17	296
Reclassification adjustments, pretax	(49)	(45)	(147)	(158)
Tax	10	9	31	33
Reclassification adjustments, net of taxes	(39)	(36)	(116)	(125)
Other comprehensive income (loss), net of taxes	(296)	159	(99)	171
Equity, ending balance	(123)	244	(123)	244
Employee Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Equity, beginning balance	(2,808)	(2,483)	(2,793)	(2,408)
Other comprehensive income (loss) before reclassification adjustments, pretax	0	29	6	(24)
Tax	(3)	(7)	(5)	(4)
Other comprehensive income (loss) before reclassification adjustments, net of taxes	(3)	22	1	(28)
Reclassification adjustments, pretax	(14)	(27)	(44)	(57)
Tax	4	5	15	10
Reclassification adjustments, net of taxes	(10)	(22)	(29)	(47)
Other comprehensive income (loss), net of taxes	(13)	0	(28)	(75)
Equity, ending balance	(2,821)	(2,483)	(2,821)	(2,483)
Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Equity, beginning balance	(2,726)	(2,502)	(2,344)	(2,433)
Other comprehensive income (loss) before reclassification adjustments, pretax	279	(252)	(103)	(288)
Tax	20	77	0	35
Other comprehensive income (loss) before reclassification adjustments, net of taxes	299	(175)	(103)	(253)
Reclassification adjustments, pretax	0	0	20	9
Tax	0	0	0	0
Reclassification adjustments, net of taxes	0	0	20	9
Other comprehensive income (loss), net of taxes	299	(175)	(83)	(244)
Equity, ending balance	$ (2,427)	$ (2,677)	$ (2,427)	$ (2,677)

Segment Reporting - Narrative (

Segment Reporting - Narrative (Details) $ in Billions	3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) segment	Sep. 30, 2023 USD ($)
Segment Reporting [Abstract]
Number of operating segments | segment			2
Sales discounts | $	$ 3.6	$ 3.1	$ 10.1	$ 9.4

Segment Reporting - Sales from

Segment Reporting - Sales from Products (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Segment Reporting Information [Line Items]
Sales	$ 16,657	$ 15,962	$ 48,544	$ 45,485
Increase in hedge revenue			156	173
Revenue related to the sale of the marketing rights			91	118
U.S.
Segment Reporting Information [Line Items]
Sales	8,736	7,715	24,089	21,393
Non-US
Segment Reporting Information [Line Items]
Sales	7,922	8,247	24,455	24,092
Operating Segments
Segment Reporting Information [Line Items]
Sales	16,430	15,663	47,838	44,789
Operating Segments | U.S.
Segment Reporting Information [Line Items]
Sales	8,714	7,615	23,980	21,258
Operating Segments | Non-US
Segment Reporting Information [Line Items]
Sales	7,716	8,048	23,858	23,531
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Sales	227	299	706	696
Corporate, Non-Segment | U.S.
Segment Reporting Information [Line Items]
Sales	22	100	109	135
Corporate, Non-Segment | Non-US
Segment Reporting Information [Line Items]
Sales	206	199	597	561
Pharmaceutical | Operating Segments
Segment Reporting Information [Line Items]
Sales	14,943	14,263	43,358	40,442
Pharmaceutical | Operating Segments | U.S.
Segment Reporting Information [Line Items]
Sales	8,227	7,153	22,563	19,840
Pharmaceutical | Operating Segments | Non-US
Segment Reporting Information [Line Items]
Sales	6,717	7,110	20,795	20,602
Pharmaceutical | Operating Segments | Keytruda
Segment Reporting Information [Line Items]
Sales	7,429	6,338	21,646	18,403
Pharmaceutical | Operating Segments | Keytruda | U.S.
Segment Reporting Information [Line Items]
Sales	4,500	3,795	13,031	11,142
Pharmaceutical | Operating Segments | Keytruda | Non-US
Segment Reporting Information [Line Items]
Sales	2,929	2,543	8,614	7,261
Pharmaceutical | Operating Segments | Alliance revenue - Lynparza
Segment Reporting Information [Line Items]
Sales	337	299	947	884
Pharmaceutical | Operating Segments | Alliance revenue - Lynparza | U.S.
Segment Reporting Information [Line Items]
Sales	161	153	449	439
Pharmaceutical | Operating Segments | Alliance revenue - Lynparza | Non-US
Segment Reporting Information [Line Items]
Sales	177	146	498	445
Pharmaceutical | Operating Segments | Alliance revenue - Lenvima
Segment Reporting Information [Line Items]
Sales	251	260	755	734
Pharmaceutical | Operating Segments | Alliance revenue - Lenvima | U.S.
Segment Reporting Information [Line Items]
Sales	173	160	523	476
Pharmaceutical | Operating Segments | Alliance revenue - Lenvima | Non-US
Segment Reporting Information [Line Items]
Sales	78	100	233	258
Pharmaceutical | Operating Segments | Welireg
Segment Reporting Information [Line Items]
Sales	139	54	349	146
Pharmaceutical | Operating Segments | Welireg | U.S.
Segment Reporting Information [Line Items]
Sales	127	51	320	141
Pharmaceutical | Operating Segments | Welireg | Non-US
Segment Reporting Information [Line Items]
Sales	12	3	29	6
Pharmaceutical | Operating Segments | Alliance Revenue - Reblozyl
Segment Reporting Information [Line Items]
Sales	100	52	261	142
Pharmaceutical | Operating Segments | Alliance Revenue - Reblozyl | U.S.
Segment Reporting Information [Line Items]
Sales	82	43	215	108
Pharmaceutical | Operating Segments | Alliance Revenue - Reblozyl | Non-US
Segment Reporting Information [Line Items]
Sales	18	10	45	33
Pharmaceutical | Operating Segments | Gardasil/Gardasil 9
Segment Reporting Information [Line Items]
Sales	2,306	2,585	7,032	7,015
Pharmaceutical | Operating Segments | Gardasil/Gardasil 9 | U.S.
Segment Reporting Information [Line Items]
Sales	1,020	838	2,045	1,718
Pharmaceutical | Operating Segments | Gardasil/Gardasil 9 | Non-US
Segment Reporting Information [Line Items]
Sales	1,285	1,746	4,988	5,297
Pharmaceutical | Operating Segments | ProQuad/M-M-R II/Varivax
Segment Reporting Information [Line Items]
Sales	703	713	1,891	1,823
Pharmaceutical | Operating Segments | ProQuad/M-M-R II/Varivax | U.S.
Segment Reporting Information [Line Items]
Sales	572	567	1,500	1,435
Pharmaceutical | Operating Segments | ProQuad/M-M-R II/Varivax | Non-US
Segment Reporting Information [Line Items]
Sales	131	146	391	388
Pharmaceutical | Operating Segments | Vaxneuvance
Segment Reporting Information [Line Items]
Sales	239	214	647	488
Pharmaceutical | Operating Segments | Vaxneuvance | U.S.
Segment Reporting Information [Line Items]
Sales	137	182	397	423
Pharmaceutical | Operating Segments | Vaxneuvance | Non-US
Segment Reporting Information [Line Items]
Sales	103	33	251	65
Pharmaceutical | Operating Segments | RotaTeq
Segment Reporting Information [Line Items]
Sales	193	156	572	584
Pharmaceutical | Operating Segments | RotaTeq | U.S.
Segment Reporting Information [Line Items]
Sales	131	108	388	381
Pharmaceutical | Operating Segments | RotaTeq | Non-US
Segment Reporting Information [Line Items]
Sales	62	48	185	203
Pharmaceutical | Operating Segments | Pneumovax 23
Segment Reporting Information [Line Items]
Sales	68	140	188	327
Pharmaceutical | Operating Segments | Pneumovax 23 | U.S.
Segment Reporting Information [Line Items]
Sales	19	42	36	105
Pharmaceutical | Operating Segments | Pneumovax 23 | Non-US
Segment Reporting Information [Line Items]
Sales	49	98	152	223
Pharmaceutical | Operating Segments | Bridion
Segment Reporting Information [Line Items]
Sales	420	424	1,315	1,413
Pharmaceutical | Operating Segments | Bridion | U.S.
Segment Reporting Information [Line Items]
Sales	339	265	1,020	841
Pharmaceutical | Operating Segments | Bridion | Non-US
Segment Reporting Information [Line Items]
Sales	81	159	296	572
Pharmaceutical | Operating Segments | Prevymis
Segment Reporting Information [Line Items]
Sales	208	157	570	430
Pharmaceutical | Operating Segments | Prevymis | U.S.
Segment Reporting Information [Line Items]
Sales	101	70	265	186
Pharmaceutical | Operating Segments | Prevymis | Non-US
Segment Reporting Information [Line Items]
Sales	107	87	305	244
Pharmaceutical | Operating Segments | Dificid
Segment Reporting Information [Line Items]
Sales	96	74	261	215
Pharmaceutical | Operating Segments | Dificid | U.S.
Segment Reporting Information [Line Items]
Sales	83	69	231	199
Pharmaceutical | Operating Segments | Dificid | Non-US
Segment Reporting Information [Line Items]
Sales	13	5	30	16
Pharmaceutical | Operating Segments | Zerbaxa
Segment Reporting Information [Line Items]
Sales	64	53	182	157
Pharmaceutical | Operating Segments | Zerbaxa | U.S.
Segment Reporting Information [Line Items]
Sales	39	29	106	86
Pharmaceutical | Operating Segments | Zerbaxa | Non-US
Segment Reporting Information [Line Items]
Sales	26	24	77	71
Pharmaceutical | Operating Segments | Noxafil
Segment Reporting Information [Line Items]
Sales	41	51	141	167
Pharmaceutical | Operating Segments | Noxafil | U.S.
Segment Reporting Information [Line Items]
Sales	1	4	9	29
Pharmaceutical | Operating Segments | Noxafil | Non-US
Segment Reporting Information [Line Items]
Sales	40	47	132	138
Pharmaceutical | Operating Segments | Alliance revenue - Adempas/Verquvo
Segment Reporting Information [Line Items]
Sales	102	92	306	259
Pharmaceutical | Operating Segments | Alliance revenue - Adempas/Verquvo | U.S.
Segment Reporting Information [Line Items]
Sales	96	96	283	249
Pharmaceutical | Operating Segments | Alliance revenue - Adempas/Verquvo | Non-US
Segment Reporting Information [Line Items]
Sales	7	(4)	22	10
Pharmaceutical | Operating Segments | Adempas
Segment Reporting Information [Line Items]
Sales	72	65	214	189
Pharmaceutical | Operating Segments | Adempas | U.S.
Segment Reporting Information [Line Items]
Sales	0	0	0	0
Pharmaceutical | Operating Segments | Adempas | Non-US
Segment Reporting Information [Line Items]
Sales	72	65	214	189
Pharmaceutical | Operating Segments | Winrevair
Segment Reporting Information [Line Items]
Sales	149	0	219	0
Pharmaceutical | Operating Segments | Winrevair | U.S.
Segment Reporting Information [Line Items]
Sales	147	0	216	0
Pharmaceutical | Operating Segments | Winrevair | Non-US
Segment Reporting Information [Line Items]
Sales	3	0	3	0
Pharmaceutical | Operating Segments | Lagevrio
Segment Reporting Information [Line Items]
Sales	383	640	843	1,236
Pharmaceutical | Operating Segments | Lagevrio | U.S.
Segment Reporting Information [Line Items]
Sales	84	0	144	0
Pharmaceutical | Operating Segments | Lagevrio | Non-US
Segment Reporting Information [Line Items]
Sales	299	640	699	1,236
Pharmaceutical | Operating Segments | Isentress/Isentress HD
Segment Reporting Information [Line Items]
Sales	102	119	302	377
Pharmaceutical | Operating Segments | Isentress/Isentress HD | U.S.
Segment Reporting Information [Line Items]
Sales	54	58	147	165
Pharmaceutical | Operating Segments | Isentress/Isentress HD | Non-US
Segment Reporting Information [Line Items]
Sales	48	61	155	212
Pharmaceutical | Operating Segments | Delstrigo
Segment Reporting Information [Line Items]
Sales	65	54	180	148
Pharmaceutical | Operating Segments | Delstrigo | U.S.
Segment Reporting Information [Line Items]
Sales	15	13	42	37
Pharmaceutical | Operating Segments | Delstrigo | Non-US
Segment Reporting Information [Line Items]
Sales	50	40	139	110
Pharmaceutical | Operating Segments | Pifeltro
Segment Reporting Information [Line Items]
Sales	42	37	123	109
Pharmaceutical | Operating Segments | Pifeltro | U.S.
Segment Reporting Information [Line Items]
Sales	31	27	86	78
Pharmaceutical | Operating Segments | Pifeltro | Non-US
Segment Reporting Information [Line Items]
Sales	12	10	37	31
Pharmaceutical | Operating Segments | Belsomra
Segment Reporting Information [Line Items]
Sales	78	58	177	176
Pharmaceutical | Operating Segments | Belsomra | U.S.
Segment Reporting Information [Line Items]
Sales	20	23	53	60
Pharmaceutical | Operating Segments | Belsomra | Non-US
Segment Reporting Information [Line Items]
Sales	58	35	124	117
Pharmaceutical | Operating Segments | Simponi
Segment Reporting Information [Line Items]
Sales	189	179	545	539
Pharmaceutical | Operating Segments | Simponi | U.S.
Segment Reporting Information [Line Items]
Sales	0	0	0	0
Pharmaceutical | Operating Segments | Simponi | Non-US
Segment Reporting Information [Line Items]
Sales	189	179	545	539
Pharmaceutical | Operating Segments | Remicade
Segment Reporting Information [Line Items]
Sales	41	45	115	144
Pharmaceutical | Operating Segments | Remicade | U.S.
Segment Reporting Information [Line Items]
Sales	0	0	0	0
Pharmaceutical | Operating Segments | Remicade | Non-US
Segment Reporting Information [Line Items]
Sales	41	45	115	144
Pharmaceutical | Operating Segments | Januvia
Segment Reporting Information [Line Items]
Sales	278	581	1,102	1,642
Pharmaceutical | Operating Segments | Januvia | U.S.
Segment Reporting Information [Line Items]
Sales	67	328	428	842
Pharmaceutical | Operating Segments | Januvia | Non-US
Segment Reporting Information [Line Items]
Sales	211	252	674	800
Pharmaceutical | Operating Segments | Janumet
Segment Reporting Information [Line Items]
Sales	204	255	679	937
Pharmaceutical | Operating Segments | Janumet | U.S.
Segment Reporting Information [Line Items]
Sales	15	43	70	182
Pharmaceutical | Operating Segments | Janumet | Non-US
Segment Reporting Information [Line Items]
Sales	190	211	610	755
Pharmaceutical | Operating Segments | Other pharmaceutical
Segment Reporting Information [Line Items]
Sales	644	568	1,796	1,758
Pharmaceutical | Operating Segments | Other pharmaceutical | U.S.
Segment Reporting Information [Line Items]
Sales	213	189	559	518
Pharmaceutical | Operating Segments | Other pharmaceutical | Non-US
Segment Reporting Information [Line Items]
Sales	426	381	1,232	1,239
Animal Health | Operating Segments
Segment Reporting Information [Line Items]
Sales	1,487	1,400	4,480	4,347
Animal Health | Operating Segments | U.S.
Segment Reporting Information [Line Items]
Sales	487	462	1,417	1,418
Animal Health | Operating Segments | Non-US
Segment Reporting Information [Line Items]
Sales	999	938	3,063	2,929
Animal Health | Operating Segments | Livestock
Segment Reporting Information [Line Items]
Sales	886	874	2,573	2,530
Animal Health | Operating Segments | Livestock | U.S.
Segment Reporting Information [Line Items]
Sales	194	205	529	543
Animal Health | Operating Segments | Livestock | Non-US
Segment Reporting Information [Line Items]
Sales	692	669	2,044	1,987
Animal Health | Operating Segments | Companion Animal
Segment Reporting Information [Line Items]
Sales	601	526	1,907	1,817
Animal Health | Operating Segments | Companion Animal | U.S.
Segment Reporting Information [Line Items]
Sales	293	257	888	875
Animal Health | Operating Segments | Companion Animal | Non-US
Segment Reporting Information [Line Items]
Sales	$ 307	$ 269	$ 1,019	$ 942

Segment Reporting - Consolidate

Segment Reporting - Consolidated Sales by Geographic Area (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenue from External Customer [Line Items]
Sales	$ 16,657	$ 15,962	$ 48,544	$ 45,485
United States
Revenue from External Customer [Line Items]
Sales	8,736	7,715	24,089	21,393
Europe, Middle East and Africa
Revenue from External Customer [Line Items]
Sales	3,583	3,327	10,661	9,978
China
Revenue from External Customer [Line Items]
Sales	1,017	1,694	4,606	5,322
Latin America
Revenue from External Customer [Line Items]
Sales	936	895	2,591	2,298
Japan
Revenue from External Customer [Line Items]
Sales	938	1,081	2,445	2,514
Asia Pacific (other than China and Japan)
Revenue from External Customer [Line Items]
Sales	823	781	2,294	2,475
Other
Revenue from External Customer [Line Items]
Sales	$ 624	$ 469	$ 1,858	$ 1,505

Segment Reporting - Reconciliat

Segment Reporting - Reconciliation of Segment Profits to Income before Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Segment Reporting Information [Line Items]
Profits	$ 4,090	$ 5,620	$ 15,766	$ 3,935
Interest income	127	73	269	295
Interest expense	(330)	(317)	(943)	(836)
Amortization			(1,720)	(1,582)
Depreciation			(1,582)	(1,326)
Research and development	(5,862)	(3,307)	(13,354)	(20,904)
Restructuring costs	(56)	(126)	(258)	(344)
Operating Segments
Segment Reporting Information [Line Items]
Profits	12,057	10,828	35,225	30,853
Operating Segments | Pharmaceutical segment
Segment Reporting Information [Line Items]
Profits	11,547	10,407	33,651	29,400
Operating Segments | Animal Health segment
Segment Reporting Information [Line Items]
Profits	510	421	1,574	1,453
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Profits	117	190	391	374
Interest income	127	73	269	295
Interest expense	(330)	(317)	(943)	(836)
Amortization	(633)	(562)	(1,720)	(1,582)
Depreciation	(467)	(401)	(1,368)	(1,175)
Research and development	(5,716)	(3,183)	(12,926)	(20,523)
Restructuring costs	(56)	(126)	(258)	(344)
Charge for Zetia antitrust litigation settlements	0	0	0	(573)
Other unallocated, net	$ (1,009)	$ (882)	$ (2,904)	$ (2,554)