Ph.D. Noubar B. Afeyan - 26 Feb 2026 Form 4 Insider Report for Generate Biomedicines, Inc. (GENB)

Signature
/s/ Noubar B. Afeyan, Ph.D.
Issuer symbol
GENB
Transactions as of
26 Feb 2026
Net transactions value
+$75,000,000
Form type
4
Filing time
02 Mar 2026, 17:42:42 UTC
Previous filing
15 Dec 2025

Reporting Owners (7)

Name Relationship Address Signature Signature date CIK
AFEYAN NOUBAR Director, 10%+ Owner 55 CAMBRIDGE PARKWAY, SUITE 800E, CAMBRIDGE /s/ Noubar B. Afeyan, Ph.D. 02 Mar 2026 0001222012
Flagship VentureLabs VI LLC 10%+ Owner 55 CAMBRIDGE PARKWAY, SUITE 800E, CAMBRIDGE Flagship VentureLabs VI LLC, By: /s/ Noubar B. Afeyan, Ph.D., Title: Sole Member and Manager of Manager of Manager of Manager 02 Mar 2026 0001725008
Flagship Pioneering Fund VI, L.P. 10%+ Owner 55 CAMBRIDGE PARKWAY, SUITE 800E, CAMBRIDGE Flagship Pioneering Fund VI, L.P., By: /s/ Noubar B. Afeyan, Ph.D., Title: Sole Member and Manager of Manager of Manager of General Partner 02 Mar 2026 0001716926
Flagship Pioneering Fund VII, L.P. 10%+ Owner 55 CAMBRIDGE PARKWAY, SUITE 800E, CAMBRIDGE Flagship Pioneering Fund VII, L.P., By: /s/ Noubar B. Afeyan, Ph.D., Title: Sole Member and Manager of Manager of Manager of General Partner 02 Mar 2026 0001805916
Nutritional Health LTP Fund, L.P. 10%+ Owner 55 CAMBRIDGE PARKWAY, SUITE 800E, CAMBRIDGE Nutritional Health LTP Fund, L.P., By: /s/ Noubar B. Afeyan, Ph.D., Title: Sole Member and Manager of Manager of Manager of General Partner 02 Mar 2026 0001780956
Flagship Pioneering Special Opportunities Fund II, L.P. 10%+ Owner 55 CAMBRIDGE PARKWAY, SUITE 800E, CAMBRIDGE Flagship Pioneering Special Opportunities Fund II, L.P., By: /s/ Noubar B. Afeyan Ph.D., Title: Sole Member and Manager of Manager of Manager of General Partner 02 Mar 2026 0001761283
FPN II, L.P. 10%+ Owner 55 CAMBRIDGE PARKWAY, SUITE 800E, CAMBRIDGE FPN II, L.P., By: /s/ Noubar B. Afeyan, Ph.D., Title: Sole Member and Manager of Manager of Manager of General Partner 02 Mar 2026 0001918834

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction GENB Common Stock Conversion of derivative security +12,723,940 12,723,940 02 Mar 2026 By Flagship Pioneering Fund VI, L.P. F1, F2
transaction GENB Common Stock Conversion of derivative security +13,702,224 13,702,224 02 Mar 2026 By Flagship Pioneering Fund VII, L.P. F1, F3
transaction GENB Common Stock Conversion of derivative security +987,491 987,491 02 Mar 2026 By Nutritional Health LTP Fund, L.P. F1, F4
transaction GENB Common Stock Conversion of derivative security +2,777,752 2,777,752 02 Mar 2026 By Flagship Pioneering Special Opportunities Fund II, L.P. F1, F5
transaction GENB Common Stock Conversion of derivative security +2,777,752 2,777,752 02 Mar 2026 By FPN II, L.P. F1, F6
transaction GENB Common Stock Purchase $25,000,000 +1,562,500 +11% $16.00 15,264,724 02 Mar 2026 By Flagship Pioneering Fund VII, L.P. F3
transaction GENB Common Stock Purchase $25,000,000 +1,562,500 +56% $16.00 4,340,252 02 Mar 2026 By FPN II, L.P. F6
transaction GENB Common Stock Purchase $25,000,000 +1,562,500 $16.00 1,562,500 02 Mar 2026 By Pioneering Medicines 02, LLC F7
holding GENB Common Stock 25,016,458 26 Feb 2026 By Flagship VentureLabs VI, LLC F8

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction GENB Stock Option (Right to Buy) Award $0 +29,561 $0.000000 29,561 26 Feb 2026 Common Stock 29,561 $16.00 Direct F9
transaction GENB Series A Preferred Stock Conversion of derivative security $0 -18,483,785 -100% $0.000000 0 02 Mar 2026 Common Stock 12,168,390 By Flagship Pioneering Fund VI, L.P. F1, F2
transaction GENB Series A Preferred Stock Conversion of derivative security $0 -17,016,215 -100% $0.000000 0 02 Mar 2026 Common Stock 11,202,248 By Flagship Pioneering Fund VII, L.P. F1, F3
transaction GENB Series A Preferred Stock Conversion of derivative security $0 -1,500,000 -100% $0.000000 0 02 Mar 2026 Common Stock 987,491 By Nutritional Health LTP Fund, L.P. F1, F4
transaction GENB Series B Preferred Stock Conversion of derivative security $0 -843,881 -100% $0.000000 0 02 Mar 2026 Common Stock 555,550 By Flagship Pioneering Fund VI, L.P. F1, F2
transaction GENB Series B Preferred Stock Conversion of derivative security $0 -1,265,822 -100% $0.000000 0 02 Mar 2026 Common Stock 833,325 By Flagship Pioneering Fund VII, L.P. F1, F3
transaction GENB Series B Preferred Stock Conversion of derivative security $0 -2,953,586 -100% $0.000000 0 02 Mar 2026 Common Stock 1,944,427 By Flagship Pioneering Special Opportunities Fund II, L.P. F1, F5
transaction GENB Series B Preferred Stock Conversion of derivative security $0 -2,109,704 -100% $0.000000 0 02 Mar 2026 Common Stock 1,388,876 By FPN II, L.P. F1, F6
transaction GENB Series C Preferred Stock Conversion of derivative security $0 -2,531,644 -100% $0.000000 0 02 Mar 2026 Common Stock 1,666,651 By Flagship Pioneering Fund VII, L.P. F1, F3
transaction GENB Series C Preferred Stock Conversion of derivative security $0 -1,265,822 -100% $0.000000 0 02 Mar 2026 Common Stock 833,325 By Flagship Pioneering Special Opportunities Fund II, L.P. F1, F5
transaction GENB Series C Preferred Stock Conversion of derivative security $0 -2,109,704 -100% $0.000000 0 02 Mar 2026 Common Stock 1,388,876 By FPN II, L.P. F1, F6
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Securities held by Flagship Pioneering Fund VI, L.P. ("Flagship Fund VI"). Flagship Pioneering Fund VI General Partner LLC ("Flagship Fund VI GP") is the general partner of Flagship Fund VI. Flagship Pioneering, LLC ("Flagship Pioneering") is the manager of Flagship Fund VI GP. Noubar B. Afeyan, Ph.D. is the ultimate control person of Flagship Pioneering. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any.
F2 Each share of Series A Preferred Stock, Series B Preferred Stock and Series C Preferred Stock (collectively, the "Preferred Stock") automatically converted into shares of the Issuer's Common Stock on a one-for-1.5190 basis upon the closing of the Issuer's initial public offering on March 2, 2026. The Preferred Stock had no expiration date.
F3 Securities held by Flagship Pioneering Fund VII, L.P. ("Flagship Fund VII"). Flagship Pioneering Fund VII General Partner LLC ("Flagship Fund VII GP") is the general partner of Flagship Fund VII. Flagship Pioneering is the manager of Flagship Fund VII GP. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any.
F4 Securities held by Nutritional Health LTP Fund, L.P. ("Nutritional LTP"). Nutritional Health LTP Fund General Partner LLC ("Nutritional LTP GP") is the general partner of Nutritional LTP. Flagship Pioneering is the manager of Nutritional LTP GP. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any.
F5 Securities held by Flagship Pioneering Special Opportunities Fund II, L.P. ("Flagship Opportunities Fund II"). Flagship Pioneering Special Opportunities Fund II General Partner LLC ("Flagship Opportunities Fund II GP") is the general partner of Flagship Opportunities Fund II. Flagship Pioneering is the manager of Flagship Opportunities Fund II GP. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any.
F6 Securities held by FPN II, L.P. ("FPN II Fund"). FPN General Partner LLC ("FPN GP") is the general partner of FPN II Fund. Flagship Pioneering is the manager of FPN GP. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any.
F7 Securities held by Pioneering Medicine 02, LLC ("PM02"). Charles R. Carelli, Jr., Chief Financial Officer of Flagship Pioneering, is the sole manager of PM02, and Flagship Fund VII is its majority equity holder. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any.
F8 Securities held by Flagship VentureLabs VI LLC ("VentureLabs VI"). Flagship VentureLabs VI Manager LLC ("VentureLabs VI Manager") is the manager of VentureLabs VI. Flagship Pioneering is the manager of VentureLabs VI Manager. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any.
F9 The shares underlying this option shall vest in full on February 19, 2027, subject to the Reporting Person's continued service on such vesting date.

Remarks:

Form 1 of 2: This is the first of two Forms 4 being filed relating to the same event. The Form 4 is being split into two filings because there are more than 10 Reporting Persons in total, and the SEC's EDGAR filing system limits a single Form 4 to a maximum of 10 Reporting Persons. Each Form 4 is filed by Designated Filer Noubar Afeyan.