Seres Therapeutics, Inc.
MCRB- Exchange
- Nasdaq
- Industry
- Pharmaceutical Preparations
- SEC CIK
- 0001609809
In the last 90 days, Seres Therapeutics, Inc. insiders filed 0 open-market purchases and 4 sales; 35 institutions reported holding it in 13F filings for Q2 2026, worth $17.9M in total; no superinvestor holds it.
13F holders, Q1 2026
Institutional positions in Seres Therapeutics, Inc. as of Mar 31, 2026. Investment managers with $100 million or more in US stocks report their long positions on Form 13F within 45 days after each quarter ends. How 13F works
- Institutional holders
- 33
- −2 vs. Q4 2025
- Shares held
- 2.31M
- +189.1K (+8.9%) vs. Q4 2025
- Total value
- $20.5M
- −$11.1M (−35.1%) vs. Q4 2025
- New holders
- 5
- 10 more added
- Sold out
- 7
- 8 more reduced
1 institution that held it in Q4 2025 haven't filed for Q1 2026 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q4 2025: new holders, sold out and not filed yet
Holders and value by quarter
Institutions reporting MCRB on Form 13F each quarter since Q1 2021, and the total value they reported. Values are as of each quarter end, so they also move with the share price.
| Quarter | Holders | Value |
|---|---|---|
| Q2 2026 | 35 | $17.9M |
| Q1 2026 | 33 | $20.5M |
| Q4 2025 | 36 | $36.4M |
| Q3 2025 | 32 | $40.9M |
| Q2 2025 | 33 | $25.4M |
| Q1 2025 | 63 | $43.1M |
| Q4 2024 | 69 | $52.5M |
| Q3 2024 | 77 | $60.1M |
| Q2 2024 | 93 | $50.0M |
| Q1 2024 | 99 | $66.3M |
| Q4 2023 | 103 | $125.4M |
| Q3 2023 | 134 | $255.6M |
| Q2 2023 | 138 | $538.1M |
| Q1 2023 | 123 | $593.9M |
| Q4 2022 | 124 | $588.2M |
| Q3 2022 | 120 | $671.6M |
| Q2 2022 | 123 | $312.7M |
| Q1 2022 | 131 | $537.2M |
| Q4 2021 | 148 | $642.8M |
| Q3 2021 | 133 | $555.1M |
| Q2 2021 | 147 | $1.93B |
| Q1 2021 | 154 | $1.85B |
Institutions, Q1 2026
Shares, value and share of portfolio for each institution holding Seres Therapeutics, Inc.; share changes are against Q4 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| Flagship Pioneering Inc. | 1,155,850 | $10.3M | 0.88% | 00.0% | Unchanged |
| Vanguard Capital Management LLC | 294,143 | $2.61M | 0.00% | +294,143 | New |
| Marshall Wace, LLP | 139,539 | $1.24M | 0.00% | +19,362+16.1% | Added |
| Vontobel Holding Ltd. | 138,468 | $1.23M | 0.00% | +35,234+34.1% | Added |
| Susquehanna International Group, LLP | 105,339 | $934.4K | 0.00% | −74,590−41.5% | Reduced |
| BlackRock, Inc. | 102,026 | $905.0K | 0.00% | −1,595−1.5% | Reduced |
| Geode Capital Management, LLC | 74,835 | $664.1K | 0.00% | −11,307−13.1% | Reduced |
| American Century Companies Inc | 62,316 | $552.7K | 0.00% | +46,045+283.0% | Added |
| Vanguard Fiduciary Trust Co | 39,643 | $351.6K | 0.00% | +39,643 | New |
| State Street Corp | 33,901 | $300.7K | 0.00% | 00.0% | Unchanged |
| Charles Schwab Investment Management Inc | 31,630 | $280.6K | 0.00% | +261+0.8% | Added |
| Lion Point Capital, LP | 31,570 | $280.0K | 1.67% | 00.0% | Unchanged |
| Morgan Stanley | 21,700 | $192.5K | 0.00% | −3,426−13.6% | Reduced |
| Two Sigma Investments, LP | 18,794 | $166.7K | 0.00% | −6,955−27.0% | Reduced |
| Northern Trust Corp | 14,765 | $131.0K | 0.00% | 00.0% | Unchanged |
| Invesco Ltd. | 14,547 | $129.0K | 0.00% | +187+1.3% | Added |
| UBS Group AG | 7,030 | $62.4K | 0.00% | +2,804+66.4% | Added |
| Barclays PLC | 6,507 | $57.7K | 0.00% | −925−12.4% | Reduced |
| SBI Securities Co., Ltd. | 3,482 | $30.9K | 0.00% | 00.0% | Unchanged |
| Simplex Trading, LLC | 3,070 | $27.2K | 0.00% | +1,838+149.2% | Added |
| Vanguard Global Advisers, LLC | 1,975 | $17.5K | 0.00% | +1,975 | New |
| FMR LLC | 1,752 | $15.5K | 0.00% | +12+0.7% | Added |
| Rachor Investment Advisory Services, LLC | 1,477 | $13.1K | 0.01% | 00.0% | Unchanged |
| Group One Trading, L.P. | 824 | $7.31K | 0.00% | +824 | New |
| Tower Research Capital LLC (TRC) | 794 | $7.04K | 0.00% | +794 | New |
| BNP Paribas Arbitrage, SA | 211 | $1.87K | 0.00% | −562−72.7% | Reduced |
| UMA Financial Services, Inc. | 142 | $1.26K | 0.00% | 00.0% | Unchanged |
| Royal Bank of Canada | 107 | $1.00K | 0.00% | +98+1,088.9% | Added |
| Wells Fargo & Company | 10 | $89 | 0.00% | −250−96.2% | Reduced |
| Sound Income Strategies, LLC | 8 | $71 | 0.00% | 00.0% | Unchanged |
| Advisor Group Holdings, Inc. | 8 | $70 | 0.00% | 00.0% | Unchanged |
| Allworth Financial LP | 4 | $36 | 0.00% | 00.0% | Unchanged |
| SRS Capital Advisors, Inc. | 6 | $18 | 0.00% | +4+200.0% | Added |
| 683 Capital Management, LLC | 0 | $0 | 0.00% | −52,314−100.0% | Sold out |
| Citadel Advisors LLC | 0 | $0 | 0.00% | −31,418−100.0% | Sold out |
| Schonfeld Strategic Advisors LLC | 0 | $0 | 0.00% | −29,097−100.0% | Sold out |
| Omers Administration Corp | 0 | $0 | 0.00% | −14,400−100.0% | Sold out |
| Goldman Sachs Group Inc | 0 | $0 | 0.00% | −14,340−100.0% | Sold out |
| ExodusPoint Capital Management, LP | 0 | $0 | 0.00% | −12,737−100.0% | Sold out |
| Bank of America Corp | 0 | $0 | 0.00% | −195−100.0% | Sold out |
| Vanguard Group Inc | – | – | – | – | Not filed |