David Michael Williams - 06 Feb 2026 Form 4 Insider Report for Merck & Co., Inc. (MRK)

Role: EVP,Chief Info&Digital Officer
Signature: /s/ Kelly E. W. Grez as Attorney-in-Fact for David Michael Williams
Issuer symbol: MRK
Transactions as of: 06 Feb 2026
Net transactions value: -$221,425
Form type: 4
Filing time: 06 Feb 2026, 16:20:14 UTC
Previous filing: 28 Jan 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Williams David Michael	EVP,Chief Info&Digital Officer	MERCK & CO., INC., 126 EAST LINCOLN AVENUE, RAHWAY	/s/ Kelly E. W. Grez as Attorney-in-Fact for David Michael Williams	06 Feb 2026	0001820958

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	MRK	Common Stock	Options Exercise	$388,100	+5,000	+16%	$77.62	35,838	06 Feb 2026	Direct
transaction	MRK	Common Stock	Sale	$609,525	-5,000	-14%	$121.90	30,838	06 Feb 2026	Direct

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	MRK	Stock Option (Right to Buy)	Options Exercise	$0	-5,000	-52%	$0.000000	4,600	06 Feb 2026	Common Stock	5,000	$77.62	Direct	F1, F2

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	Exercise price and holdings reflect the adjustments that occurred as of June 2, 2021 in connection with the Organon & Co. ("Organon") spin-off as described in the registration statement on Form 10 filed with the SEC by Organon (the "Form 10"). As reported in the Form 10, all Merck stock option awards outstanding as of immediately prior to the distribution date were converted on the distribution date into adjusted Merck awards for Merck employees to preserve the same intrinsic value and general terms and conditions (including vesting) as were in place immediately prior to the adjustments.
F2	The option vests and becomes exercisable in three equal installments on 5/3/2020, 5/3/2021 and 5/3/2022.

Content

Exercise price and holdings reflect the adjustments that occurred as of June 2, 2021 in connection with the Organon & Co. ("Organon") spin-off as described in the registration statement on Form 10 filed with the SEC by Organon (the "Form 10"). As reported in the Form 10, all Merck stock option awards outstanding as of immediately prior to the distribution date were converted on the distribution date into adjusted Merck awards for Merck employees to preserve the same intrinsic value and general terms and conditions (including vesting) as were in place immediately prior to the adjustments.

The option vests and becomes exercisable in three equal installments on 5/3/2020, 5/3/2021 and 5/3/2022.