Q2 2026 13F · SEC CIK 1400240
Flagship Pioneering, LLC
Hedge fundFiled 2026-08-14 for Q2 2026. Open the filing ↗ · All SEC filings ↗
- Reported 13F value
- $1.5B
- Reported positions
- 5
- Top holdings a year, 3 yrs
- -31.2%
- Average holding period
- 2.2 yrs
Flagship Pioneering, LLC is a hedge fund that reported 5 positions worth $1.5B in its Q2 2026 13F, filed 2026-08-14. Its largest holdings were Generate Biomedicines Inc (GENB, 68.7%), Moderna Inc (MRNA, 21.1%), Sana Biotechnology Inc (SANA, 5.7%). A portfolio copying its top holdings returned -31.2% a year over the last 3 years, against 20.4% for the S&P 500.
Flagship Pioneering, LLC holdings all 5 positions.
Weights are shares of the filer's total reported 13F value, compared with Q1 2026. Share changes may reflect splits; weight changes also reflect price moves. A 13F shows long US-listed positions only, up to 135 days after the fact.
| Stock | % of 13F value | Share change | Reported value |
|---|---|---|---|
| GENBGenerate Biomedicines Inc | 68.7% | +0.0% | $1.1B |
| MRNAModerna Inc | 21.1% | +0.0% | $324.4M |
| SANASana Biotechnology Inc | 5.7% | +0.0% | $87.3M |
| FHTXFoghorn Therapeutics Inc | 4.0% | +0.0% | $61.8M |
| MCRBSeres Therapeutics Inc | 0.6% | +0.0% | $9.1M |
What Flagship Pioneering, LLC bought and sold in Q2 2026, against Q1 2026.
New positions
No new positions among the largest holdings.
Added to
No position grew by more than 5%.
Reduced
No position shrank by more than 5%.
Sold out
Nothing sold out.
Share counts compared with the Q1 2026 13F; a split also changes share counts.
How the holdings did against the S&P 500.
- 1 year
- —
- 3 years
- -31.2% /yr
- S&P 500 +20.4%
- 5 years
- -37.5% /yr
- S&P 500 +10.1%
A portfolio of the filer's 20 largest 13F positions, weighted by value, bought the trading day after each 13F was filed and held until the next one was: what copying this filer could have earned. 13Fs show long US-listed positions only, so this is an estimate of the stock picks, not the fund's reported returns.
Reported 13F value by quarter.
| Quarter | 13F value | Positions |
|---|---|---|
| Q2 2026 | $1.5B | 5 |
| Q1 2026 | $1.2B | 5 |
| Q4 2024 | $334.2M | 5 |
| Q3 2024 | $591.9M | 6 |
| Q2 2024 | $843.4M | 6 |
| Q1 2024 | $1.5B | 7 |
| Q4 2023 | $1.3B | 7 |
| Q3 2023 | $1.4B | 9 |
| Q2 2023 | $2.2B | 10 |
| Q1 2023 | $2.6B | 11 |
| Q4 2022 | $3.1B | 12 |
| Q3 2022 | $2.4B | 12 |
Questions about Flagship Pioneering, LLC's portfolio
What stocks does Flagship Pioneering, LLC own?
Flagship Pioneering, LLC's latest 13F, for Q2 2026 and filed Aug 14, 2026, lists 5 positions worth $1.5B. The largest are Generate Biomedicines Inc (GENB) at 68.7%, Moderna Inc (MRNA) at 21.1%, Sana Biotechnology Inc (SANA) at 5.7%, Foghorn Therapeutics Inc (FHTX) at 4.0% and Seres Therapeutics Inc (MCRB) at 0.6%.
What did Flagship Pioneering, LLC buy last quarter?
Flagship Pioneering, LLC opened no new positions and grew none by more than 5% among its largest holdings in Q2 2026.
What did Flagship Pioneering, LLC sell last quarter?
Flagship Pioneering, LLC sold out of nothing and cut no large position by more than 5% in Q2 2026.
How has Flagship Pioneering, LLC's portfolio performed?
A portfolio copying Flagship Pioneering, LLC's 20 largest 13F holdings each quarter, from the day each filing was public, returned -31.2% a year over the last 3 years, against +20.4% for the S&P 500. Over 5 years: -37.5% a year against +10.1%.
When is Flagship Pioneering, LLC's next 13F filing due?
13F filings are due 45 days after each quarter ends. Flagship Pioneering, LLC's filing for the quarter ending Sep 30, 2026 is due by Nov 14, 2026; this page updates the day after it is published.