Seres TherapeuticsMCRB
13F holders, Q3 2025 (September 30)32holders −1
9new positions
10sold out
1famous investor
$19.24avg. 13F price*
At the end of Q3 2025, 32 institutions reported holding Seres Therapeutics Inc. (MCRB) in their 13F filings, down 1 from Q2 2025. 9 opened new positions and 10 sold out. The largest holders were Flagship Pioneering, LLC ($22.2M), Vanguard Group Inc. ($6.0M) and Marshall Wace, LLP ($2.4M). One famous investor held it Ken Griffin (0.0% of Citadel Advisors's portfolio).
- Company
- Seres Therapeutics Inc.
- CUSIP
- 81750R201
- Latest filing quarter
- Q2 2026
History
Number of 13F holders
Total Exit/New Position Q2 2025 → Q3 2025
| Institutions | Total Value | |
|---|---|---|
| New Positions | 9 | $2.0M |
| Exits | 10 | $925K |
All 13F filers, Q2 2025 → Q3 2025: 210,795 shares bought and 369,898 shares sold, net −159,103 shares. Counts holders who added, trimmed, opened or closed a position; split-adjusted.
Ownership 32 holders
| Flagship Pioneering, LLC | 7.60% | No change | 1,155,850 | $22.2M |
| Vanguard Group Inc. | 0.00% | Add +6.8% | 311,889 | $6.0M |
| Marshall Wace, LLP | 0.00% | Add +37.4% | 125,600 | $2.4M |
| BlackRock, Inc. | 0.00% | Add +0.7% | 102,060 | $2.0M |
| Vontobel Holding Ltd. | 0.01% | Add +22.6% | 98,511 | $1.9M |
| Geode Capital Management, LLC | 0.00% | Reduce -7.2% | 84,982 | $1.6M |
| Charles Schwab Investment Management Inc. | 0.00% | Reduce -10.0% | 31,403 | $604K |
| Citadel Advisors | 0.00% | New | 30,885 | $594K |
| State Street Corp. | 0.00% | Add +10.8% | 29,731 | $572K |
| Schonfeld Strategic Advisors LLC | 0.00% | New | 28,942 | $557K |
| Lion Point Capital, LP | 2.97% | Add +59.3% | 27,138 | $522K |
| J. Goldman & Co LP | 0.02% | New | 27,000 | $519K |
| Morgan Stanley | 0.00% | Add +133.9% | 18,334 | $353K |
| UBS Group AG | 0.00% | Add +68.4% | 12,682 | $244K |
| Northern Trust Corp. | 0.00% | Reduce -19.7% | 12,101 | $233K |
| Invesco Ltd. | 0.00% | New | 10,442 | $201K |
| Bank of America Corp. | 0.00% | Add +2772.6% | 5,343 | $103K |
| SBI Securities Co., Ltd. | 0.00% | No change | 3,482 | $67K |
| Simplex Trading, LLC | 0.00% | New | 2,807 | $54K |
| Citigroup Inc. | 0.00% | Add +29022.2% | 2,621 | $50K |
| FMR LLC | 0.00% | Reduce -99.3% | 1,882 | $36K |
| Barclays PLC | 0.00% | New | 1,408 | $27K |
| Royal Bank of Canada | 0.00% | Reduce -95.7% | 296 | $6K |
| BNP Paribas Financial Markets | 0.00% | Reduce -30.5% | 212 | $4K |
| Physician Wealth Advisors, Inc. | 0.00% | No change | 142 | $3K |
| JPMorgan Chase & Co. | 0.00% | No change | 65 | $1K |
| US Bancorp \de | 0.00% | Reduce -52.0% | 12 | $231 |
| Wells Fargo & Company | 0.00% | No change | 10 | $192 |
| Sound Income Strategies, LLC | 0.00% | New | 8 | $156 |
| Osaic Holdings, Inc. | 0.00% | No change | 8 | $151 |
| Federation des caisses Desjardins du Quebec | 0.00% | New | 3 | $58 |
| Arax Advisory Partners | 0.00% | New | 2 | $38 |
"% of holder's portfolio" is MCRB's weight in each manager's 13F, not the share of Seres Therapeutics Inc. the manager owns.