Interim Financial Statements Basis of Presentation The interim Condensed Consolidated Financial Statements of Regeneron Pharmaceuticals, Inc. and its subsidiaries ("Regeneron," "Company," "we," "us," and "our") have been prepared in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all information and disclosures necessary for a presentation of the Company's financial position, results of operations, and cash flows in conformity with accounting principles generally accepted in the United States of America. In the opinion of management, these financial statements reflect all normal recurring adjustments and accruals necessary for a fair statement of the Company's condensed consolidated financial statements for such periods. The results of operations for any interim period are not necessarily indicative of the results for the full year. The December 31, 2019 Condensed Consolidated Balance Sheet data were derived from audited financial statements, but do not include all disclosures required by accounting principles generally accepted in the United States of America. These financial statements should be read in conjunction with the financial statements and notes thereto contained in the Companys Annual Report on Form 10-K for the year ended December 31, 2019. Certain reclassifications have been made to prior period amounts to conform with the current period's presentation. Effective January 1, 2020, we changed the presentation of cost reimbursements from collaborators who are not deemed to be our customers from collaboration revenue to a reduction of the corresponding operating expense ( i.e. , either Research and development or Selling, general, and administrative) incurred by us. We also changed the presentation of amounts recognized in connection with up-front and development milestone payments received from collaboration revenue to other operating income. We made these changes in presentation because we believe the new presentation is preferable, as it better reflects the nature of the Companys costs incurred and revenues earned pursuant to arrangements with collaborators and enhances the comparability of our financial statements with industry peers. The change in presentation has been applied retrospectively. The tables below present the impact of the change on the Companys previously-filed Consolidated Balance Sheet as of December 31, 2019, the Condensed Consolidated Statement of Operations for the three and nine months ended September 30, 2019, and the Condensed Consolidated Statement of Cash Flows for the nine months ended September 30, 2019. The Companys previously-filed balance sheet has been updated to reflect the addition of the caption Other liabilities for the presentation of up-front and development milestones paid by collaborators that are deferred. There was no impact on the Companys previously-filed Consolidated Statements of Stockholders Equity. December 31, 2019 Balance Sheet Data: As Previously Reported Adjustments As Revised Accrued expenses and other current liabilities $ 1,086.8 $ 124.6 $ 1,211.4 Deferred revenue - Sanofi (current) $ 395.5 $ (85.0) $ 310.5 Deferred revenue - other (current) $ 196.2 $ (124.6) $ 71.6 Other liabilities - Sanofi (current)  $ 85.0 $ 85.0 Deferred revenue - Sanofi (noncurrent) $ 509.7 $ (482.0) $ 27.7 Deferred revenue - other (noncurrent) $ 109.3 $ (31.7) $ 77.6 Other liabilities - Sanofi (noncurrent)  $ 482.0 $ 482.0 Other noncurrent liabilities $ 286.0 $ 31.7 $ 317.7 Three Months Ended September 30, 2019 Nine Months Ended September 30, 2019 Statement of Operations Data: As Previously Reported Adjustments As Revised As Previously Reported Adjustments As Revised Sanofi collaboration revenue $ 404.2 $ (229.2) $ 175.0 $ 999.7 $ (766.9) $ 232.8 Bayer collaboration revenue $ 302.8 $ (9.2) $ 293.6 $ 868.0 $ (33.2) $ 834.8 Other revenue $ 103.1 $ (66.3) $ 36.8 $ 278.2 $ (199.7) $ 78.5 Total revenues $ 2,048.4 $ (304.7) $ 1,743.7 $ 5,693.9 $ (999.8) $ 4,694.1 Research and development $ 663.4 $ (137.4) $ 526.0 $ 2,353.5 $ (455.9) $ 1,897.6 Selling, general, and administrative $ 419.9 $ (115.5) $ 304.4 $ 1,248.0 $ (357.9) $ 890.1 Cost of collaboration and contract manufacturing (1) $ 110.7 $ (1.1) $ 109.6 $ 304.5 $ (14.9) $ 289.6 Other operating (income) expense, net  $ (50.7) $ (50.7)  $ (171.1) $ (171.1) Total operating expenses $ 1,309.9 $ (304.7) $ 1,005.2 $ 4,159.8 $ (999.8) $ 3,160.0 (1) In addition to the reclassification of certain amounts in connection with the change in accounting presentation described above, the Company also reclassified certain immaterial reimbursements that were previously classified as collaboration revenue to Cost of collaboration and contract manufacturing. Nine Months Ended September 30, 2019 Cash Flows Data: As Previously Reported Adjustments As Revised Cash flows from operating activities: Increase in deferred revenue $ 375.8 $ (209.0) $ 166.8 Increase in accounts payable, accrued expenses, and other liabilities $ 119.9 $ 209.0 $ 328.9 Use of Estimates The preparation of financial statements in conformity with generally accepted accounting principles requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. The extent to which the COVID-19 pandemic may directly or indirectly impact our business, financial condition, and results of operations is highly uncertain and subject to change. We considered the potential impact of the COVID-19 pandemic on our estimates and assumptions and there was not a material impact to our condensed consolidated financial statements as of and for the three and nine months ended September 30, 2020; however, actual results could differ from those estimates and there may be changes to our estimates in future periods. Recently Adopted Accounting Standards We adopted Accounting Standards Update 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments ("ASU 2016-13"), as of January 1, 2020. ASU 2016-13 requires an entity to measure and recognize expected credit losses for certain financial instruments, including trade receivables, as an allowance that reflects the entity's current estimate of credit losses expected to be incurred. For available-for-sale debt securities with unrealized credit losses, the standard requires allowances to be recorded through net income instead of directly reducing the amortized cost of the investment under the previous other-than-temporary impairment model. The adoption of this standard did not have a material impact on our financial statements or a significant impact on our internal controls.