THERMO FISHER SCIENTIFIC INC.

1 UNITED STATES SECURITIES AND EXCHANGE COMMISSIONW ashington, 20549 FORM 10-K 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 Commission file number 1-8002 THERMO FISHER SCIENTIFIC INC.(Exact name of Registrant as specified in its charter)Delaware04-2209186(State of incorporation)( Employer Identification No.)168 Third AvenueWaltham, Massachusetts 02451(Address of principal executive offices) (Zip Code)Registrant s telephone number, including area code: (781) 622-1000 Securities registered pursuant to Section 12(b) of the Act.

2 Title of each classTrading Symbol(s)Name of each exchange on which registeredCommon Stock, $ par valueTMONew York Stock Notes due 2022 TMO 22 ANew York Stock Notes due 2024 TMO 24 ANew York Stock Notes due 2025 TMO 25 BNew York Stock Notes due 2025 TMO 25 New York Stock Notes due 2026 TMO 26 ANew York Stock Notes due 2027 TMO 27 New York Stock Notes due 2027 TMO 27 BNew York Stock Notes due 2028 TMO 28 ANew York Stock Notes due 2028 TMO 28 New York Stock Notes due 2029 TMO 29 New York Stock Notes due 2031 TMO 31 New York Stock Notes due 2032 TMO 32 New York Stock Notes due 2037 TMO 37 New York Stock Notes due 2039 TMO 39 New York Stock Notes due 2049 TMO 49 New York Stock ExchangeSecurities registered pursuant to Section 12(g) of the Act.

3 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 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 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 duringthe preceding 12 months.

4 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 ExchangeAct. Large accelerated filer Accelerated filer Non-accelerated filer Smaller reporting company Emerging growth company 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 As of June 26, 2020, the aggregate market value of the voting stock held by nonaffiliates of the Registrant was approximately $138,639,543,000 (based on the last reported saleof common stock on the New York Stock Exchange Composite Tape reporting system on June 26, 2020).As of February 6, 2021, the Registrant had 393,793,362 shares of Common Stock INCORPORATED BY REFERENCES ections of THERMO FISHER s definitive Proxy Statement for the 2021 Annual Meeting of Shareholders are incorporated by reference into Parts II and III of this FISHER SCIENTIFIC REPORT ON FORM 10-KFOR THE FISCAL YEAR ENDED DECEMBER 31, 2020 TABLE OF CONTENTSPagePART IItem Factors15 Item Staff Comments23 Item Proceedings23 Item Safety Disclosures23 PART IIItem for the Registrant s Common Equity.

6 Related Stockholder Matters and Issuer Purchases of Equity Securities23 Item s Discussion and Analysis of Financial Condition and Results of Operations24 Item and Qualitative Disclosures About Market Risk33 Item Statements and Supplementary Data34 Item in and Disagreements with Accountants on Accounting and Financial Disclosure34 Item and Procedures34 Item Information34 PART IIIItem , Executive Officers and Corporate Governance35 Item Compensation35 Item Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters35 Item Relationships and Related Transactions, and Director Independence35 Item Accountant Fees and Services35 PART IVItem and Financial Statement Schedules35 Item 10-K Summary352 THERMO FISHER SCIENTIFIC IItem 1.

7 BusinessGeneral Development of BusinessThermo FISHER SCIENTIFIC Inc. (also referred to in this document as THERMO FISHER , we, the company, or the registrant ) is the world leader in servingscience. Our Mission is to enable our customers to make the world healthier, cleaner and safer. We serve more than 400,000 customers working in pharmaceuticaland biotech companies, hospitals and clinical diagnostic labs, universities, research institutions and government agencies, as well as environmental, industrialquality and process control settings. Our global team of more than 80,000 colleagues delivers an unrivaled combination of innovative technologies, purchasingconvenience and pharmaceutical services through our industry-leading brands, including THERMO SCIENTIFIC , Applied Biosystems, Invitrogen, FISHER SCIENTIFIC ,Unity Lab Services and continuously increase our depth of capabilities in technologies, software and services, and leverage our extensive global channels to address ourcustomers emerging needs.

8 We do this through organic investments in research and development and through acquisitions. Our goal is to make our customersmore productive in an increasingly competitive business environment, and enable them to solve their challenges, from complex research to improved patient care,environmental and process monitoring, and consumer StatementsForward-looking statements, within the meaning of Section 21E of the Securities Exchange Act of 1934 (the Exchange Act), are made throughout this AnnualReport on Form 10-K. Any statements contained herein that are not statements of historical fact may be deemed to be forward-looking statements, includingwithout limitation statements regarding: projections of revenues, expenses, earnings, margins, tax rates, tax provisions, cash flows, pension and benefit obligationsand funding requirements, our liquidity position; cost reductions, restructuring activities, new product and service developments, competitive strengths or marketposition, acquisitions or divestitures; growth, declines and other trends in markets we sell into; new or modified laws, regulations and accounting pronouncements.

9 Outstanding claims, legal proceedings, tax audits and assessments and other contingent liabilities; foreign currency exchange rates and fluctuations in those rates;general economic and capital markets conditions; the timing of any of the foregoing; assumptions underlying any of the foregoing; the expected impact of theCOVID-19 pandemic on the company s business; and any other statements that address events or developments that THERMO FISHER intends or believes will or mayoccur in the future. Without limiting the foregoing, the words believes, anticipates, plans, expects, seeks, estimates, and similar expressions areintended to identify forward-looking statements, although not all forward-looking statements are accompanied by such words.

10 While the company may elect toupdate forward-looking statements in the future, it specifically disclaims any obligation to do so, even if the company s estimates change, and readers should notrely on those forward-looking statements as representing the company s views as of any date subsequent to the date of the filing of this number of important factors could cause the results of the company to differ materially from those indicated by such forward-looking statements, includingthose detailed under the heading, Risk Factors in Part I, Item Segments and ProductsWe report our business in four segments Life Sciences Solutions, Analytical Instruments, Specialty Diagnostics, and Laboratory Products and 2020, we worked with our customers to respond to the COVID-19 pandemic.