| 10.16*** | | | Third Amended and Restated Lease and Remedies Agreement, dated as of March 27, 2023, between Old Saw Mill Holdings LLC, as lessee, and BA Leasing BSC, LLC, as lessor. (Incorporated by reference from the Form 8-K for the Registrant, filed March 29, 2023.) | | |
| 10.17*** | | | Third Amended and Restated Guaranty, dated as of March 27, 2023, made by the Registrant, Regeneron Healthcare Solutions, Inc., and Regeneron Genetics Center LLC, as guarantors. (Incorporated by reference from the Form 8-K for the Registrant, filed March 29, 2023.) | | |
| 10.18** | | | Master Agreement, dated as of April 8, 2019, by and between the Registrant and Alnylam Pharmaceuticals, Inc. (Incorporated by reference from the Form 10-Q for the Registrant, for the quarter ended June 30, 2019, filed August 6, 2019.) | | |
| 10.18.1** | | | Form of Co-Co Collaboration Agreement (Exhibit B to Master Agreement contained in Exhibit 10.18). | | |
| 10.18.2** | | | Form of License Agreement (Exhibit C to Master Agreement contained in Exhibit 10.18). | | |
| 10.18.3** | | | Amendment No. 1 to Master Agreement, dated as of April 10, 2023, by and between the Registrant and Alnylam Pharmaceuticals, Inc. (Incorporated by reference from the Form 10-Q for the Registrant, for the quarter ended June 30, 2023, filed August 3, 2023.) | | |
| 10.18.4** | | | Amendment No. 2 to Master Agreement, dated as of March 7, 2024, by and between the Registrant and Alnylam Pharmaceuticals, Inc. (Incorporated by reference from the Form 10-Q for the Registrant, for the quarter ended March 31, 2024, filed May 2, 2024.) | | |
| 10.18.5** | | | Amendment No. 3 to Master Agreement, dated as of August 1, 2024, by and between the Registrant and Alnylam Pharmaceuticals, Inc. (Incorporated by reference from the Form 10-Q for the Registrant, for the quarter ended September 30, 2024, filed October 31, 2024.) | | |
| 19.1 | | | Insider Trading Policy. (Incorporated by reference from the Form 10-K for the Registrant, for the year ended December 31, 2024, filed February 5, 2025.) | | |
| 21.1 | | | Subsidiaries of the Registrant. | | |
| 23.1 | | | Consent of PricewaterhouseCoopers LLP, Independent Registered Public Accounting Firm. | | |
| 24.1 | | | Power of Attorney (included on the signature page of this Annual Report on Form 10-K). | | |
| 31.1 | | | Certification of Principal Executive Officer pursuant to Rule 13a-14(a) under the Securities Exchange Act of 1934. | | |
| 31.2 | | | Certification of Principal Financial Officer pursuant to Rule 13a-14(a) under the Securities Exchange Act of 1934. | | |
| 32 | | | Certification of Principal Executive Officer and Principal Financial Officer pursuant to 18 U.S.C. Section 1350. | | |
| 97.1 | | | Clawback Policy. (Incorporated by reference from the Form 10-K for the Registrant, for the year ended December 31, 2023, filed February 5, 2024.) | | |
| 101 | | | Interactive Data Files pursuant to Rule 405 of Regulation S-T formatted in Inline Extensible Business Reporting Language ("Inline XBRL"): (i) the Registrant's Consolidated Balance Sheets as of December 31, 2025 and 2024; (ii) the Registrant's Consolidated Statements of Operations and Comprehensive Income for the years ended December 31, 2025, 2024, and 2023; (iii) the Registrant's Consolidated Statements of Stockholders’ Equity for the years ended December 31, 2025, 2024, and 2023; (iv) the Registrant's Consolidated Statements of Cash Flows for the years ended December 31, 2025, 2024, and 2023; and (v) the notes to the Registrant's Consolidated Financial Statements. | | |
| 104 | | | Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101). | | |
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