Flagship Pioneering, LLC - 31 Mar 2026 SCHEDULE 13G Report for Generate Biomedicines, Inc. Common Stock, $0.001 par value per share (GENB)

Filing manager
Flagship Pioneering, LLC
Reporting owner
Afeyan Noubar
Security
Generate Biomedicines, Inc. Common Stock, $0.001 par value per share
Beneficially owned shares
62,701,915 shares
Ownership signal CIK-linked ownership evidence from parsed SEC filings. 2 signals
Large-stake signal

Form

SCHEDULE 13G

Passive or exempt beneficial ownership filing.

Ownership

49%

Beneficial ownership of this reported class.

Shares

62,701,915 shares

Shares beneficially owned as disclosed.

Event date

31 Mar 2026

Date tied to the ownership event or amendment.

Accepted by SEC

15 May 2026

EDGAR acceptance date.

How to read this large-stake filing
  • Schedule 13D/G filings focus on beneficial ownership stakes, not a full portfolio.
  • Compare this filing with the holder history and issuer page before treating the percentage as a current position.
  • Use amendments to understand whether the disclosed stake increased, decreased, or changed reporting status.
Class ownership
49%
Subject security Names, identifiers, and filing context for this profile. 2 source fields
Symbol
GENB
Shares outstanding
128,224,775 shares
Source evidence Original filing metadata and source links for verification. 4 source fields
SEC form
SCHEDULE 13G
Accepted by SEC
15 May 2026, 16:00:03 UTC
Event date
31 Mar 2026
Source filing
View source filing

Key filing fact

Flagship Pioneering, LLC disclosed 49% ownership in Generate Biomedicines, Inc. Common Stock, $0.001 par value per share (GENB) on 31 Mar 2026.

Key facts

  • Flagship Pioneering, LLC filed SCHEDULE 13G for Generate Biomedicines, Inc. Common Stock, $0.001 par value per share (GENB).
  • Disclosed ownership: 49%.
  • Date of event: 31 Mar 2026.

Change

  • No earlier schedule filing is available for direct comparison.
  • Current filing was accepted on 15 May 2026, 16:00.

Research use

  • This page turns one Schedule 13D/G filing into a quick large-stake read before the raw reporting-person rows.
  • Use the linked SEC filing as the source of truth for ownership percentages, shares, and reporting-party details.

Evidence

Backed by Schedule 13D/13G

Beneficial ownership values are sourced from the original SEC Schedule 13D/13G filing.

View source filing

Reporting persons

Disclosed reporting parties (15)

Names, ownership percentages, voting power, signatures, titles, and CIKs as disclosed in this Schedule 13D/G filing.

Name Ownership Shares owned Sole voting power Shared voting power Signature Title CIK
Flagship Pioneering Fund VI, L.P. 9.9% 12,723,940 0 12,723,940 /s/ Noubar B. Afeyan, Ph.D. Noubar B. Afeyan, Ph.D., Sole Member and Manager of Manager of Manager of General Partner
Flagship Pioneering Fund VI General Partner LLC 9.9% 12,723,940 0 12,723,940 /s/ Noubar B. Afeyan, Ph.D. Noubar B. Afeyan, Ph.D., Sole Member and Manager of Manager of Manager
Pioneering Medicines 02, LLC 1.2% 1,562,500 0 1,562,500 /s/ Charles R. Carelli, Jr. Charles R. Carelli, Jr., Manager
Flagship Pioneering Fund VII, L.P. 13% 16,827,224 0 16,827,224 /s/ Noubar B. Afeyan, Ph.D. Noubar B. Afeyan, Ph.D., Title: Sole Member and Manager of Manager of Manager of General Partner
Flagship Pioneering Fund VII General Partner LLC 13% 16,827,224 0 16,827,224 /s/ Noubar B. Afeyan, Ph.D. Noubar B. Afeyan, Ph.D., Title: Sole Member and Manager of Manager of Manager
Nutritional Health LTP Fund, L.P. 0.8% 987,491 0 987,491 /s/ Noubar B. Afeyan, Ph.D. Noubar B. Afeyan, Ph.D., Sole Member and Manager of Manager of Manager of General Partner
Nutritional Health LTP Fund General Partner LLC 0.8% 987,491 0 987,491 /s/ Noubar B. Afeyan, Ph.D. Noubar B. Afeyan, Ph.D., Sole Member and Manager of Manager of Manager
Flagship Pioneering Special Opportunities Fund II, L.P. 2.2% 2,777,752 0 2,777,752 /s/ Noubar B. Afeyan, Ph.D. Noubar B. Afeyan Ph.D., Sole Member and Manager of Manager of Manager of General Partner
Flagship Pioneering Special Opportunities Fund II General Partner LLC 2.2% 2,777,752 0 2,777,752 /s/ Noubar B. Afeyan, Ph.D. Noubar B. Afeyan Ph.D., Sole Member and Manager of Manager of Manager
FPN II, L.P. 3.4% 4,340,252 0 4,340,252 /s/ Noubar B. Afeyan, Ph.D. Noubar B. Afeyan, Ph.D., Sole Member and Manager of Manager of Manager of General Partner
FPN General Partner LLC 3.4% 4,340,252 0 4,340,252 /s/ Noubar B. Afeyan, Ph.D. Noubar B. Afeyan, Ph.D., Sole Member and Manager of Manager of Manager
Flagship VentureLabs VI, LLC 20% 25,016,458 0 25,016,458 /s/ Noubar B. Afeyan, Ph.D. Noubar B. Afeyan, Ph.D., Sole Member and Manager of Manager of Manager of Manager
Flagship VentureLabs VI Manager LLC 20% 25,016,458 0 25,016,458 /s/ Noubar B. Afeyan, Ph.D. Noubar B. Afeyan, Ph.D., Sole Member and Manager of Manager of Manager
Flagship Pioneering, LLC 49% 62,673,117 0 62,673,117 /s/ Noubar B. Afeyan, Ph.D. Noubar B. Afeyan, Ph.D., Sole Member and Manager of Manager
Afeyan Noubar 49% 62,701,915 28,798 62,673,117 /s/ Noubar B. Afeyan, Ph.D. Noubar B. Afeyan, Ph.D.
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