Managers / Q1 2025 · view latest →
Flagship Pioneering, LLC
CIK 0001400240 · 55 CAMBRIDGE PARKWAY, SUITE 800E, CAMBRIDGE, MA, 02142 · 617 868-1888
Reported Value
$236M
Q1 2025
Positions
8
Filings on Record
30
2019–present window
Filed
May 15, 2025
original filing
Summary
Flagship Pioneering, Llc reported $236M in U.S.-listed holdings across 8 positions for Q1 2025.
The portfolio is heavily concentrated: MRNA alone accounts for 55.7% of reported value.
Compared with Q4 2024, the fund opened 0 new positions and exited 1.
Reported Value by Quarter
13F Reported Value
Portfolio Composition
By security type
Composition data arrives with ticker enrichment.
Quarter-over-Quarter Changes full breakdown →
Holdings — Q1 2025
Filing History
| Quarter | Reported Value | Positions | Filed | Type | Links |
|---|---|---|---|---|---|
| Q1 2026 | $1.2B | 7 | May 15, 2026 | 13F-HR | changes · EDGAR ↗ |
| Q4 2025 | $324M | 6 | Feb 17, 2026 | 13F-HR | changes · EDGAR ↗ |
| Q3 2025 | $293M | 8 | Nov 14, 2025 | 13F-HR | changes · EDGAR ↗ |
| Q2 2025 | $268M | 8 | Aug 14, 2025 | 13F-HR | changes · EDGAR ↗ |
| Q1 2025 | $236M | 8 | May 15, 2025 | 13F-HR | changes · EDGAR ↗ |
| Q4 2024 | $334M | 10 | Feb 14, 2025 | 13F-HR | changes · EDGAR ↗ |
| Q3 2024 | $592M | 12 | Nov 14, 2024 | 13F-HR | changes · EDGAR ↗ |
| Q2 2024 | $843M | 12 | Aug 14, 2024 | 13F-HR | changes · EDGAR ↗ |
| Q1 2024 | $1.5B | 13 | May 15, 2024 | 13F-HR | changes · EDGAR ↗ |
| Q4 2023 | $1.3B | 13 | Feb 14, 2024 | 13F-HR | changes · EDGAR ↗ |
| Q3 2023 | $1.4B | 18 | Nov 14, 2023 | 13F-HR | changes · EDGAR ↗ |
| Q2 2023 | $2.2B | 20 | Aug 14, 2023 | 13F-HR | changes · EDGAR ↗ |
| Q1 2023 | $2.6B | 22 | May 15, 2023 | 13F-HR | changes · EDGAR ↗ |
| Q4 2022 | $3.13T | 25 | Feb 14, 2023 | 13F-HR | changes · EDGAR ↗ |
| Q3 2022 | $2.4B | 35 | Nov 14, 2022 | 13F-HR | changes · EDGAR ↗ |
| Q2 2022 | $2.7B | 33 | Aug 15, 2022 | 13F-HR | changes · EDGAR ↗ |
| Q1 2022 | $4.3B | 38 | May 16, 2022 | 13F-HR | changes · EDGAR ↗ |
| Q4 2021 | $6.5B | 38 | Feb 14, 2022 | 13F-HR | changes · EDGAR ↗ |
| Q3 2021 | $9.5B | 38 | Nov 15, 2021 | 13F-HR | changes · EDGAR ↗ |
| Q2 2021 | $7.8B | 33 | Aug 16, 2021 | 13F-HR | changes · EDGAR ↗ |
| Q1 2021 | $6.2B | 33 | May 17, 2021 | 13F-HR | changes · EDGAR ↗ |
| Q4 2020 | $5.5B | 30 | Feb 16, 2021 | 13F-HR | changes · EDGAR ↗ |
| Q3 2020 | $3.6B | 17 | Nov 16, 2020 | 13F-HR | changes · EDGAR ↗ |
| Q2 2020 | $3.4B | 17 | Aug 13, 2020 | 13F-HR | changes · EDGAR ↗ |
| Q1 2020 | $2.1B | 17 | May 14, 2020 | 13F-HR | changes · EDGAR ↗ |
| Q4 2019 | $1.8B | 19 | Feb 13, 2020 | 13F-HR | changes · EDGAR ↗ |
| Q3 2019 | $1.8B | 20 | Nov 14, 2019 | 13F-HR | changes · EDGAR ↗ |
| Q2 2019 | $2.3B | 20 | Aug 13, 2019 | 13F-HR | changes · EDGAR ↗ |
| Q1 2019 | $2.6B | 15 | May 14, 2019 | 13F-HR | changes · EDGAR ↗ |
| Q4 2018 | $2.0B | 12 | Feb 13, 2019 | 13F-HR | changes · EDGAR ↗ |
Other Included Managers
This filing reports holdings on behalf of 3 additional managers.
- Flagship Ventures Fund V General Partner LLC028-18466
- Flagship Ventures Fund IV General Partner LLC028-17238
- Noubar Afeyan028-19988
13F filings are due up to 45 days after quarter end, so holdings shown here lag the fund’s current book. Source: original SEC filing on EDGAR ↗.