2 unchanged sentences
From time to time, our officers (as defined in Rule 16a–1(f)) and directors may enter into Rule 10b5-1 or non-Rule 10b5-1 trading arrangements (as each such term is defined in Item 408 of Regulation S-K).
−Removed: During the three months ended September 30, 2025, none of the Company’s directors or officers adopted , modified or terminated a plan or other arrangement intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) or any non-Rule 10b5-1 trading arrangements (as defined in Item 408(c) of Regulation S-K).
+Added: During the three months ended March 31, 2026, none of the Company’s directors or officers adopted , modified or terminated a plan or other arrangement intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) or any non-Rule 10b5-1 trading arrangements (as defined in Item 408(c) of Regulation S-K).
(a) Exhibits.
−Removed: Exhibit number Exhibit table
+Added: Description of Exhibit
3.1 Third Amended and Restated Certificate of Incorporation of Prime Medicine, Inc.
−Removed: (incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K, filed with the SEC on October 24, 2022).
3.2 Certificate of Amendment to Third Amended and Restated Certificate of Incorporation of Prime Medicine, Inc.
−Removed: (incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K, filed with the SEC on June 12, 2024).
Second Amended and Restated Bylaws of Prime Medicine, Inc.
−Removed: (incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K, filed with the SEC on May 21, 2024).
−Removed: Amendment No.
−Removed: 4 to License Agreement, dated September 11 , 202 5 , between The Broad Institute, Inc.
−Removed: and the Registrant
−Removed: Amendment No.
−Removed: 5 to License Agreement, dated September 11, 2025, between The Broad Institute, Inc.
−Removed: and the Registrant
−Removed: Side Letter No.
−Removed: 2 to License Agreement, dated September 11, 2025, between The Broad Institute, Inc.
−Removed: and the Registrant
−Removed: 31.1* Certification of Principal Executive Officer and Principal Financial Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Securities Exchange Act of 1934, as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
−Removed: 32.1** Certification of Principal Executive Officer and Principal Financial Officer Pursuant to 18 U.S.C.
+Added: Third Amended and Restated Non-Employee Director Compensation Policy
+Added: Certification of Principal Executive Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Securities Exchange Act of 1934, as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
+Added: Certification of Principal Financial Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Securities Exchange Act of 1934, as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
+Added: 32.1** Certification of Principal Executive Officer Pursuant to 18 U.S.C.
Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
−Removed: 101.INS* Inline XBRL Instance Document
−Removed: 101.SCH* Inline XBRL Taxonomy Extension Schema Document
−Removed: 101.CAL* Inline XBRL Taxonomy Extension Calculation Linkbase Document
−Removed: 101.DEF* Inline XBRL Taxonomy Extension Definition Linkbase Document
−Removed: 101.LAB* Inline XBRL Taxonomy Extension Label Linkbase Document
−Removed: 101.PRE* Inline XBRL Taxonomy Extension Presentation Linkbase Document
−Removed: 104* Cover Page Interactive Data File (embedded within the Inline XBRL document)
+Added: 32.2** Certification of Principal Financial Officer Pursuant to 18 U.S.C.
+Added: Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
+Added: Inline XBRL Instance Document X
+Added: Inline XBRL Taxonomy Extension Schema Document X
+Added: Inline XBRL Taxonomy Extension Calculation Linkbase Document X
+Added: Inline XBRL Taxonomy Extension Definition Linkbase Document X
+Added: Inline XBRL Taxonomy Extension Label Linkbase Document X
+Added: Inline XBRL Taxonomy Extension Presentation Linkbase Document X
+Added: Cover Page Interactive Data File (embedded within the Inline XBRL document) X
__________________
−Removed: * Filed herewith.
−Removed: ** The certification furnished in Exhibit 32.1 hereto is deemed to accompany this Quarterly Report on Form 10-Q and will not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended.
+Added: * Indicates a management contract or any compensatory plan, contract or arrangement.
+Added: ** The certification furnished in Exhibit 32.1 and Exhibit 32.2 hereto are deemed to accompany this Quarterly Report on Form 10-Q and will not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended.
Such certification will not be deemed to be incorporated by reference into any filings under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, except to the extent that the Registrant specifically incorporates it by reference.
−Removed: † Portions of this exhibit (indicated by asterisks) have been omitted in accordance with Item 601(b)(10) of Regulation S-K.
(b) Financial Statement Schedules.
2 unchanged sentences
/s/ Allan Reine
−Removed: November 7, 2025 Allan Reine
+Added: May 7, 2026 Allan Reine
Chief Executive Officer
−Removed: (Principal Executive Officer and Principal Financial Officer)
+Added: (Principal Executive Officer)
+Added: May 7, 2026 By:
+Added: /s/ Svetlana Ni Makhni
+Added: Svetlana Ni Makhni
+Added: Chief Financial Officer
+Added: (Principal Financial Officer)
Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.