SEC INSIDER TRANSACTIONS

Merck & Co., Inc. (MRK) Insider Transactions

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MRK · Merck & Co., Inc.

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OR within codes/roles; AND between categories. Roles apply to buyers and sellers. Owner predicates match the same owner. Missing values fail numeric/date filters. Value is quantity × reported price for non-derivative rows only; derivative values are unknown. Amendments stay separate; joint owners do not duplicate rows.

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Stale snapshot · Covered: filings 2026-05-14 to 2026-11-13 · 29 filings · fetched 2026-11-13T18:57:54Z

Recent reported activity

0purchase rows on this page

13sale rows on this page

52matching filing rows

Purchases and sales count original non-derivative P and S rows. Awards, gifts, exercises, derivatives and amendments are shown separately and are not described as market purchases.

Transaction / filed	Reporting owner(s)	Code / security	Quantity	Price as filed	Ownership	Source
2026-11-01Filed 2026-11-03	DIAZ PAUL JDirector Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 1-for-1 F2 Phantom stock units are to be settled 100% in cash upon reporting person's termination of service in accordance with a distribution schedule elected pursuant to the terms of the Plan for Deferred Payment of Directors' Compensation. F3 The price reported is the closing price of Merck Common Stock on the business day immediately prior to the effective date of the Director's service. References: F1, F3, F2	A Award / grantPhantom Stock · Derivative	613.073A	149.52	Direct	Form 4 ↗0000310158-26-000245
2026-09-30Filed 2026-10-01	Seidman Christine EDirector Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 1-for-1 F2 Phantom stock units are to be settled 100% in cash upon reporting person's termination of service in accordance with a distribution schedule elected pursuant to the terms of the Plan for Deferred Payment of Directors' Compensation. F3 Holdings include shares acquired in dividend reinvestment transactions. References: F1, F2, F3	A Award / grantPhantom Stock · Derivative	55.9149A	145.31	Direct	Form 4 ↗0000310158-26-000234
2026-09-30Filed 2026-10-01	Karsanbhai Surendralal LancaDirector Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 1-for-1 F2 Phantom stock units are to be settled 100% in cash upon reporting person's termination of service in accordance with a distribution schedule elected pursuant to the terms of the Plan for Deferred Payment of Directors' Compensation. F3 Holdings include shares acquired in dividend reinvestment transactions. References: F1, F2, F3	A Award / grantPhantom Stock · Derivative	111.8299A	145.31	Direct	Form 4 ↗0000310158-26-000232
2026-09-30Filed 2026-10-01	Coe Mary EllenDirector Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 1-for-1 F2 Phantom stock units are to be settled 100% in cash upon reporting person's termination of service in accordance with a distribution schedule elected pursuant to the terms of the Plan for Deferred Payment of Directors' Compensation. F3 Holdings include shares acquired in dividend reinvestment transactions. References: F1, F2, F3	A Award / grantPhantom Stock · Derivative	206.4552A	145.31	Direct	Form 4 ↗0000310158-26-000230
2026-08-13Filed 2026-08-13	Guindo ChirfiOfficer · EVP, Access, Policy & Comms Filing context Reported filing row; may be amended. Do not sum filings blindly. References:	S Sale (market/private)Common Stock · Non-derivative	10,000D	135	Direct	Form 4 ↗0000310158-26-000223
2026-08-12Filed 2026-08-13	Zachary JenniferOfficer · EVP, General Counsel Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $133.0300 to $133.5000, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F2 The options vested and became exercisable in equal installments on 5/2/2024, 5/2/2025 and 5/2/2026. F3 The options vest and become exercisable in equal installments on 4/29/2026, 4/29/2027, and 4/29/2028. References: F3	M Exercise / conversionStock Option (Right to Buy) · Derivative	13,433D	0	Direct	Form 4 ↗0000310158-26-000221
2026-08-12Filed 2026-08-13	Zachary JenniferOfficer · EVP, General Counsel Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $133.0300 to $133.5000, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F2 The options vested and became exercisable in equal installments on 5/2/2024, 5/2/2025 and 5/2/2026. F3 The options vest and become exercisable in equal installments on 4/29/2026, 4/29/2027, and 4/29/2028. References: F2	M Exercise / conversionStock Option (Right to Buy) · Derivative	41,494D	0	Direct	Form 4 ↗0000310158-26-000221
2026-08-12Filed 2026-08-13	Zachary JenniferOfficer · EVP, General Counsel Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $133.0300 to $133.5000, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F2 The options vested and became exercisable in equal installments on 5/2/2024, 5/2/2025 and 5/2/2026. F3 The options vest and become exercisable in equal installments on 4/29/2026, 4/29/2027, and 4/29/2028. References: F1	S Sale (market/private)Common Stock · Non-derivative	80,315D	133.4557	Direct	Form 4 ↗0000310158-26-000221
2026-08-12Filed 2026-08-13	Zachary JenniferOfficer · EVP, General Counsel Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $133.0300 to $133.5000, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F2 The options vested and became exercisable in equal installments on 5/2/2024, 5/2/2025 and 5/2/2026. F3 The options vest and become exercisable in equal installments on 4/29/2026, 4/29/2027, and 4/29/2028. References:	M Exercise / conversionCommon Stock · Non-derivative	13,433A	84.71	Direct	Form 4 ↗0000310158-26-000221
2026-08-12Filed 2026-08-13	Zachary JenniferOfficer · EVP, General Counsel Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $133.0300 to $133.5000, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F2 The options vested and became exercisable in equal installments on 5/2/2024, 5/2/2025 and 5/2/2026. F3 The options vest and become exercisable in equal installments on 4/29/2026, 4/29/2027, and 4/29/2028. References:	M Exercise / conversionCommon Stock · Non-derivative	41,494A	117.89	Direct	Form 4 ↗0000310158-26-000221
2026-08-12Filed 2026-08-12	DeLuca Richard R.Officer · EVP&Pres, Merck Animal Heallth Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $130.0000 to $130.9500, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F2 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.9800, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F3 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $132.0000 to $132.6514, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F4 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.9950, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F5 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $132.0000 to $132.0700, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. References: F5	S Sale (market/private)Common Stock · Non-derivative	600D	132.0367	Direct	Form 4 ↗0000310158-26-000219
2026-08-12Filed 2026-08-12	DeLuca Richard R.Officer · EVP&Pres, Merck Animal Heallth Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $130.0000 to $130.9500, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F2 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.9800, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F3 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $132.0000 to $132.6514, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F4 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.9950, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F5 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $132.0000 to $132.0700, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. References: F4	S Sale (market/private)Common Stock · Non-derivative	11,099D	131.6128	Direct	Form 4 ↗0000310158-26-000219
2026-08-11Filed 2026-08-12	DeLuca Richard R.Officer · EVP&Pres, Merck Animal Heallth Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $130.0000 to $130.9500, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F2 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.9800, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F3 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $132.0000 to $132.6514, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F4 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.9950, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F5 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $132.0000 to $132.0700, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. References: F3	S Sale (market/private)Common Stock · Non-derivative	5,427D	132.3496	Direct	Form 4 ↗0000310158-26-000219
2026-08-11Filed 2026-08-12	DeLuca Richard R.Officer · EVP&Pres, Merck Animal Heallth Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $130.0000 to $130.9500, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F2 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.9800, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F3 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $132.0000 to $132.6514, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F4 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.9950, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F5 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $132.0000 to $132.0700, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. References: F2	S Sale (market/private)Common Stock · Non-derivative	7,410D	131.3313	Direct	Form 4 ↗0000310158-26-000219
2026-08-10Filed 2026-08-12	DeLuca Richard R.Officer · EVP&Pres, Merck Animal Heallth Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $130.0000 to $130.9500, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F2 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.9800, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F3 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $132.0000 to $132.6514, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F4 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.9950, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F5 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $132.0000 to $132.0700, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. References: F1	S Sale (market/private)Common Stock · Non-derivative	20,784D	130.4345	Direct	Form 4 ↗0000310158-26-000219
2026-08-06Filed 2026-08-10	DeLuca Richard R.Officer · EVP&Pres, Merck Animal Heallth Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.0700, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F2 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $130.0000 to $130.9200, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F3 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.0300, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. References: F3	S Sale (market/private)Common Stock · Non-derivative	300D	131.0233	Direct	Form 4 ↗0000310158-26-000217
2026-08-06Filed 2026-08-10	DeLuca Richard R.Officer · EVP&Pres, Merck Animal Heallth Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.0700, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F2 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $130.0000 to $130.9200, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F3 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.0300, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. References: F2	S Sale (market/private)Common Stock · Non-derivative	4,945D	130.2312	Direct	Form 4 ↗0000310158-26-000217
2026-08-06Filed 2026-08-10	DeLuca Richard R.Officer · EVP&Pres, Merck Animal Heallth Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.0700, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F2 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $130.0000 to $130.9200, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. F3 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $131.0000 to $131.0300, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote. References: F1	S Sale (market/private)Common Stock · Non-derivative	805D	131.0216	Direct	Form 4 ↗0000310158-26-000217
2026-08-06Filed 2026-08-07	Guindo ChirfiOfficer · EVP, Access, Policy & Comms Filing context Reported filing row; may be amended. Do not sum filings blindly. References:	S Sale (market/private)Common Stock · Non-derivative	15,000D	131	Direct	Form 4 ↗0000310158-26-000213
2026-08-05Filed 2026-08-07	Maraldo David R.Officer · EVP & Pres. MMD Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $128.6400 to $128.8500, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in the footnote. F2 The option vested and became exercisable in three equal installments on 5/4/2022, 5/4/2023, and 5/4/2024. F3 The option vested and become exercisable in three equal installments on 5/3/2023, 5/3/2024, and 5/3/2025. F4 The options vest and become exercisable in three equal installments on 4/29/2026, 4/29/2027, and 4/29/2028. References: F4	M Exercise / conversionStock Option (Right to Buy) · Derivative	2,686D	0	Direct	Form 4 ↗0000310158-26-000215
2026-08-05Filed 2026-08-07	Maraldo David R.Officer · EVP & Pres. MMD Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $128.6400 to $128.8500, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in the footnote. F2 The option vested and became exercisable in three equal installments on 5/4/2022, 5/4/2023, and 5/4/2024. F3 The option vested and become exercisable in three equal installments on 5/3/2023, 5/3/2024, and 5/3/2025. F4 The options vest and become exercisable in three equal installments on 4/29/2026, 4/29/2027, and 4/29/2028. References: F3	M Exercise / conversionStock Option (Right to Buy) · Derivative	9,709D	0	Direct	Form 4 ↗0000310158-26-000215
2026-08-05Filed 2026-08-07	Maraldo David R.Officer · EVP & Pres. MMD Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $128.6400 to $128.8500, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in the footnote. F2 The option vested and became exercisable in three equal installments on 5/4/2022, 5/4/2023, and 5/4/2024. F3 The option vested and become exercisable in three equal installments on 5/3/2023, 5/3/2024, and 5/3/2025. F4 The options vest and become exercisable in three equal installments on 4/29/2026, 4/29/2027, and 4/29/2028. References: F2	M Exercise / conversionStock Option (Right to Buy) · Derivative	6,311D	0	Direct	Form 4 ↗0000310158-26-000215
2026-08-05Filed 2026-08-07	Maraldo David R.Officer · EVP & Pres. MMD Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $128.6400 to $128.8500, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in the footnote. F2 The option vested and became exercisable in three equal installments on 5/4/2022, 5/4/2023, and 5/4/2024. F3 The option vested and become exercisable in three equal installments on 5/3/2023, 5/3/2024, and 5/3/2025. F4 The options vest and become exercisable in three equal installments on 4/29/2026, 4/29/2027, and 4/29/2028. References: F1	S Sale (market/private)Common Stock · Non-derivative	2,686D	128.7179	Direct	Form 4 ↗0000310158-26-000215
2026-08-05Filed 2026-08-07	Maraldo David R.Officer · EVP & Pres. MMD Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $128.6400 to $128.8500, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in the footnote. F2 The option vested and became exercisable in three equal installments on 5/4/2022, 5/4/2023, and 5/4/2024. F3 The option vested and become exercisable in three equal installments on 5/3/2023, 5/3/2024, and 5/3/2025. F4 The options vest and become exercisable in three equal installments on 4/29/2026, 4/29/2027, and 4/29/2028. References:	M Exercise / conversionCommon Stock · Non-derivative	2,686A	84.71	Direct	Form 4 ↗0000310158-26-000215
2026-08-05Filed 2026-08-07	Maraldo David R.Officer · EVP & Pres. MMD Filing context Reported filing row; may be amended. Do not sum filings blindly. F1 The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $128.6400 to $128.8500, inclusive. The reporting person undertakes to provide to Merck & Co., Inc., any security holder of Merck & Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in the footnote. F2 The option vested and became exercisable in three equal installments on 5/4/2022, 5/4/2023, and 5/4/2024. F3 The option vested and become exercisable in three equal installments on 5/3/2023, 5/3/2024, and 5/3/2025. F4 The options vest and become exercisable in three equal installments on 4/29/2026, 4/29/2027, and 4/29/2028. References: F1	S Sale (market/private)Common Stock · Non-derivative	9,709D	128.7179	Direct	Form 4 ↗0000310158-26-000215

Imported instruments only. Joint owners do not multiply transactions. Amendments are separate filing rows, not additional trades. No aggregate trade totals are implied.