Seres TherapeuticsMCRB
13F holders, Q4 2025 (December 31)36holders +4
8new positions
5sold out
1famous investor
$14.90avg. 13F price*
At the end of Q4 2025, 36 institutions reported holding Seres Therapeutics Inc. (MCRB) in their 13F filings, up 4 from Q3 2025. 8 opened new positions and 5 sold out. The largest holders were Flagship Pioneering, LLC ($17.2M), Vanguard Group Inc. ($4.8M) and Susquehanna International Group, LLP ($2.7M). 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 Q3 2025 → Q4 2025
| Institutions | Total Value | |
|---|---|---|
| New Positions | 8 | $4.7M |
| Exits | 5 | $571K |
All 13F filers, Q3 2025 → Q4 2025: 365,012 shares bought and 50,766 shares sold, net +314,246 shares. Counts holders who added, trimmed, opened or closed a position; split-adjusted.
Ownership 36 holders
| Flagship Pioneering, LLC | 5.32% | No change | 1,155,850 | $17.2M |
| Vanguard Group Inc. | 0.00% | Add +4.0% | 324,214 | $4.8M |
| Susquehanna International Group, LLP | 0.00% | New | 179,929 | $2.7M |
| Marshall Wace, LLP | 0.00% | Reduce -4.3% | 120,177 | $1.8M |
| BlackRock, Inc. | 0.00% | Add +1.5% | 103,621 | $1.5M |
| Vontobel Holding Ltd. | 0.01% | Add +4.8% | 103,234 | $1.5M |
| Geode Capital Management, LLC | 0.00% | Add +1.4% | 86,142 | $1.3M |
| 683 Capital Management, LLC | 0.07% | New | 52,314 | $778K |
| State Street Corp. | 0.00% | Add +14.0% | 33,901 | $504K |
| Lion Point Capital, LP | 2.43% | Add +16.3% | 31,570 | $470K |
| Citadel Advisors | 0.00% | Add +1.7% | 31,418 | $468K |
| Charles Schwab Investment Management Inc. | 0.00% | Reduce -0.1% | 31,369 | $467K |
| Schonfeld Strategic Advisors LLC | 0.00% | Add +0.5% | 29,097 | $433K |
| Two Sigma Investments, LP | 0.00% | New | 25,749 | $383K |
| Morgan Stanley | 0.00% | Add +37.0% | 25,126 | $374K |
| American Century Companies Inc. | 0.00% | New | 16,271 | $242K |
| Northern Trust Corp. | 0.00% | Add +22.0% | 14,765 | $220K |
| OMERS ADMINISTRATION Corp | 0.00% | New | 14,400 | $214K |
| Invesco Ltd. | 0.00% | Add +37.5% | 14,360 | $214K |
| Goldman Sachs Group Inc. | 0.00% | New | 14,340 | $213K |
| ExodusPoint Capital Management, LP | 0.00% | New | 12,737 | $190K |
| Barclays PLC | 0.00% | Add +427.8% | 7,432 | $111K |
| UBS Group AG | 0.00% | Reduce -66.7% | 4,226 | $63K |
| SBI Securities Co., Ltd. | 0.00% | No change | 3,482 | $52K |
| FMR LLC | 0.00% | Reduce -7.5% | 1,740 | $26K |
| Rachor Investment Advisory Services, LLC | 0.01% | — | 1,477 | $22K |
| Simplex Trading, LLC | 0.00% | Reduce -56.1% | 1,232 | $18K |
| BNP Paribas Financial Markets | 0.00% | Add +264.6% | 773 | $12K |
| Wells Fargo & Company | 0.00% | Add +2500.0% | 260 | $4K |
| Bank of America Corp. | 0.00% | Reduce -96.3% | 195 | $3K |
| Physician Wealth Advisors, Inc. | 0.00% | No change | 142 | $2K |
| Sound Income Strategies, LLC | 0.00% | No change | 8 | $128 |
| Osaic Holdings, Inc. | 0.00% | No change | 8 | $119 |
| Allworth Financial LP | 0.00% | New | 4 | $60 |
| Arax Advisory Partners | 0.00% | No change | 2 | $30 |
| Royal Bank of Canada | 0.00% | Reduce -97.0% | 9 | $0 |
"% of holder's portfolio" is MCRB's weight in each manager's 13F, not the share of Seres Therapeutics Inc. the manager owns.