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As filed with the Securities and Exchange Commission on February 25, 2021

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D. C. 20549

_________________________________

FORM 10-K

(MARK ONE)

			☒			Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

For the Fiscal Year Ended December 31, 2020

OR

			☐			Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

For the transition period from                  to                 

Commission File No. 1-6571

_________________________________

Merck & Co., Inc.

2000 Galloping Hill Road

Kenilworth

New Jersey

07033

(908) 740-4000

New Jersey			22-1918501
(State or other jurisdiction of incorporation)			(I.R.S Employer Identification No.)

Number of shares of Common Stock ($0.50 par value) outstanding as of January 31, 2021: 2,530,315,668.

Aggregate market value of Common Stock ($0.50 par value) held by non-affiliates on June 30, 2020 based on closing price on June 30, 2020: $195,461,000,000.

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.     Yes ☒    No ☐

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    Yes ☐    No ☒

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  ☒ No  ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).    Yes  ☒ No  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act. (Check One):

Table of Contents

									Page
Part I
Item 1.			Business						1
Item 1A.			Risk Factors						26
			Cautionary Factors that May Affect Future Results						41
Item 1B.			Unresolved Staff Comments						42
Item 2.			Properties						42
Item 3.			Legal Proceedings						43
Item 4.			Mine Safety Disclosures						43
			Executive Officers of the Registrant						44
Part II
Item 5.			Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities						45
Item 7.			Management’s Discussion and Analysis of Financial Condition and Results of Operations						47
Item 7A.			Quantitative and Qualitative Disclosures About Market Risk						78
Item 8.			Financial Statements and Supplementary Data						79
			(a)			Financial Statements			79
						Notes to Consolidated Financial Statements			83
						Report of Independent Registered Public Accounting Firm			136
Item 9.			Changes in and Disagreements with Accountants on Accounting and Financial Disclosure						138
Item 9A.			Controls and Procedures						138
			Management’s Report						138
Item 9B.			Other Information						139
Part III
Item 10.			Directors, Executive Officers and Corporate Governance						140
Item 11.			Executive Compensation						140
Item 12.			Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters						141
Item 13.			Certain Relationships and Related Transactions, and Director Independence						141
Item 14.			Principal Accountant Fees and Services						141
Part IV
Item 15.			Exhibits and Financial Statement Schedules						142
Item 16.			Form 10-K Summary						146
			Signatures						147