PFIZER INC.

1 UNITED STATES SECURITIES AND EXCHANGE COMMISSIONW ashington, 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 TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from toCommission file number 1-3619 PFIZER INC.(Exact name of registrant as specified in its charter)Delaware13-5315170(State or other jurisdiction of incorporation or organization)( Employer Identification Number)235 East 42nd Street, New York, New York 10017(Address of principal executive offices) (zip code)(212) 733-2323(Registrant s telephone number, including area code)Securities registered pursuant to Section 12(b) of the Act:Title of each classTrading Symbol(s)Name of each exchange on which registeredCommon Stock, $.

2 05 par valuePFENew York Stock Notes due 2022 PFE22 New York Stock Notes due 2027 PFE27 New York Stock ExchangeSecurities registered pursuant to Section 12(g) of the Act: NoneIndicate 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 12months (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.

3 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( 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 growthcompany. See the definitions of large accelerated filer, accelerated filer , smaller reporting company and emerging growth company in Rule 12b-2 of the Exchange Accelerated filer Accelerated filer Non-accelerated filer Smaller reporting company Emerging growth company If an emerging growth company.

4 Indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financialaccounting standards provided pursuant to Section 13(a) of the Exchange Act. Indicate by check mark whether the registrant has filed a report on and attestation to its management s assessment of the effectiveness of its internal control over financialreporting under Section 404(b) of the Sarbanes-Oxley Act (15 7262(b)) by the registered public accounting firm that prepared or issued its audit report.

5 Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes No The aggregate market value of the voting stock held by non-affiliates of the registrant, computed by reference to the closing price as of the last business day of the registrant smost recently completed second fiscal quarter, June 28, 2020, was approximately $169 billion. This excludes shares of common stock held by directors and executive officersat June 28, 2020. Exclusion of shares held by any person should not be construed to indicate that such person possesses the power, directly or indirectly, to direct or cause thedirection of the management or policies of the registrant, or that such person is controlled by or under common control with the registrant.

6 The registrant has no non-votingcommon number of shares outstanding of the registrant s common stock as of February 23, 2021 was 5,577,629,491 shares of common stock, all of one INCORPORATED BY REFERENCEP ortions of the Proxy Statement for the 2021 Annual Meeting of ShareholdersPart IIITABLE OF CONTENTS PageDefined TermsiForward-Looking Information and Factors that May Affect Future ResultsiiiPART I1 ITEM 1. BUSINESS1 About Pfizer1 Commercial Operations1 Collaboration and Co-Promotion Agreements2 Research and Development3 International Operations4 Sales and Marketing4 Patents and Other Intellectual Property Rights5 Competition6 Pricing Pressures and Managed Care Organizations7 Raw Materials8 Government Regulation and Price Constraints8 Environmental Matters10 Human Capital10 Available Information11 ITEM 1A.

7 RISK FACTORS11 ITEM 1B. UNRESOLVED STAFF COMMENTSN/AITEM 2. PROPERTIES20 ITEM 3. LEGAL PROCEEDINGS20 ITEM 4. MINE SAFETY DISCLOSURESN/AINFORMATION ABOUT OUR EXECUTIVE OFFICERS20 PART II21 ITEM 5. MARKET FOR THE COMPANY S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES21 ITEM 6. SELECTED FINANCIAL DATA23 ITEM 7. MANAGEMENT S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS23 ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK48 ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA49 ITEM 9.

8 CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE109 ITEM 9A. CONTROLS AND PROCEDURES109 ITEM 9B. OTHER INFORMATIONN/APART III112 ITEM 10. DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE112 ITEM 11. EXECUTIVE COMPENSATION112 ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS112 ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE112 ITEM 14. PRINCIPAL ACCOUNTING FEES AND SERVICES112 PART IV113 ITEM 15. EXHIBITS, FINANCIAL STATEMENT SCHEDULES11315(a)(1) Financial Statements11315(a)(2) Financial Statement Schedules11315(a)(3) Exhibits113 ITEM 16.

9 FORM 10-K SUMMARY116N/A = Not ApplicableDEFINED TERMSU nless the context requires otherwise, references to PFIZER , the Company, we, us or our in this Form 10-K (defined below) refer to PFIZER Inc. and its subsidiaries. Thefinancial information included in our consolidated financial statements for our subsidiaries operating outside the is as of and for the year ended November 30 for each yearpresented. PFIZER 's fiscal year-end for subsidiaries is as of and for the year ended December 31 for each year presented. References to Notes in this Form 10-K are tothe Notes to the consolidated financial statements in Item 8.

10 Financial Statements and Supplementary Data in this Form 10-K. We also have used several other terms in thisForm 10-K, most of which are explained or defined Financial ReportExhibit 13 to the Annual Report on Form 10-K for the fiscal year ended December 31, 2018 Form 10-KThis Annual Report on Form 10-K for the fiscal year ended December 31, 2020 Proxy StatementProxy Statement for the 2021 Annual Meeting of Shareholders, which will be filed no later than 120 days after December 31, 2020 AbbVieAbbVie benefit obligation represents the present value of the benefit obligation earned through the end of the year but doesnot factor in future compensation increasesACA (also referred to as Legislation)