Seres Therapeutics Inc (MCRB)
Institutional ownership reported to the SEC as of Q2 2026, across 32 quarters.
Institutions report 2,270,378 shares against 9,941,261 outstanding. Shares only - option lines are excluded, which is why this can be compared with the company at all. The count comes from the cover page of the company's own most recent report, so it is dated when that was filed rather than at quarter end.
Calls and puts are the parts of reported value carried in derivative lines rather than shares, and they point in opposite directions: a manager holding calls is positioned for the security, one holding puts against it - or hedging shares they already own, which is why index funds carry so many. Most sites add the two together and report one figure, which averages away the only interesting part.
Holders
| Filer | Value | Shares | Their book | Held | Change |
|---|---|---|---|---|---|
| Flagship Pioneering, LLC | $9.1M | 1,155,850 | 0.59% | 5q | HELD |
| VANGUARD CAPITAL MANAGEMENT LLC | $2.3M | 287,776 | 0.00% | 2q | -2.2%-$50.2K |
| MARSHALL WACE, LLP | $1.4M | 172,245 | 0.00% | 5q | +23.4%+$258.1K |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | $1.1M incl. $591.0K options CALL+PUT | 58,328 | 0.00% | 5q | -44.6%-$847.2K |
| Vontobel Holding Ltd. | $970.3K | 122,975 | 0.00% | 5q | -11.2%-$122.2K |
| BlackRock, Inc. | $875.8K | 111,000 | 0.00% | 5q | +8.8%+$70.8K |
| GEODE CAPITAL MANAGEMENT, LLC | $631.3K | 79,974 | 0.00% | 5q | +6.9%+$40.6K |
| CITADEL ADVISORS LLC | $426.1K incl. $343.2K options PUT | 10,504 | 0.00% | 5q | HELD |
| VANGUARD FIDUCIARY TRUST CO | $384.1K | 48,685 | 0.00% | 2q | +22.8%+$71.3K |
| STATE STREET CORP | $267.5K | 33,901 | 0.00% | 5q | HELD |
| Lion Point Capital, LP | $249.1K | 31,570 | 1.19% | 5q | HELD |
| GROUP ONE TRADING LLC | $245.5K incl. $216.2K options CALL+PUT | 3,714 | 0.00% | 5q | +350.7%+$191.0K |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC | $245.0K | 31,049 | 0.00% | 5q | -1.8%-$4.6K |
| AMERICAN CENTURY COMPANIES INC | $223.4K | 28,313 | 0.00% | 3q | -54.6%-$268.3K |
| SIMPLEX TRADING, LLC | $221.7K incl. $185.4K options CALL+PUT | 4,598 | 0.00% | 5q | +49.8%+$73.7K |
| XTX Topco Ltd | $163.6K | 20,732 | 0.00% | new | NEW |
| GOLDMAN SACHS GROUP INC | $120.2K | 15,229 | 0.00% | new | NEW |
| NORTHERN TRUST CORP | $116.5K | 14,765 | 0.00% | 5q | HELD |
| Invesco Ltd. | $102.4K | 12,974 | 0.00% | 4q | -10.8%-$12.4K |
| MORGAN STANLEY | $95.8K | 12,138 | 0.00% | 5q | -44.1%-$75.4K |
| SBI Securities Co., Ltd. | $33.0K | 4,182 | 0.00% | 6q | +20.1%+$5.5K |
| JPMORGAN CHASE & CO | $28.3K | 3,636 | 0.00% | new | NEW |
| Vanguard Global Advisers, LLC | $15.6K | 1,975 | 0.00% | 2q | HELD |
| FMR LLC | $12.1K | 1,528 | 0.00% | 5q | -12.8%-$1.8K |
| Rachor Investment Advisory Services, LLC | $11.7K | 1,477 | 0.01% | 3q | HELD |
| UBS Group AG | $3.8K | 484 | 0.00% | 5q | -93.1%-$51.6K |
| Tower Research Capital LLC (TRC) | $2.5K | 316 | 0.00% | 2q | -60.2%-$3.8K |
| BNP PARIBAS FINANCIAL MARKETS | $1.7K | 211 | 0.00% | 5q | HELD |
| BARCLAYS PLC | $1.3K | 167 | 0.00% | 4q | -97.4%-$50.0K |
| Continuum Advisory, LLC | $371 | 47 | 0.00% | new | NEW |
| WELLS FARGO & COMPANY/MN | $79 | 10 | 0.00% | 5q | HELD |
| OSAIC HOLDINGS, INC. | $63 | 8 | 0.00% | 5q | HELD |
| Larson Financial Group LLC | $39 | 5 | 0.00% | new | NEW |
| WHITTIER TRUST CO OF NEVADA INC | $8 | 1 | 0.00% | new | NEW |
| ROYAL BANK OF CANADA | $0 | 11 | 0.00% | 2q | -89.7% |
What the company announced
Form 8-K filings from the last 120 days, showing only the items worth a reader's attention. Earnings releases, exhibit attachments and general disclosures are filed constantly and are left out. Filed is when the SEC received it; event is the date the company says the thing happened.
| Filed | Event date | What | Source |
|---|---|---|---|
| 2026-10-26 | 2026-10-22 | Directors or officers departed or appointed | filing |
| 2026-08-04 | 2026-07-31 | Material agreement entered Material agreement terminated | filing |
Quarter by quarter
Coverage begins with the quarter ending 2018-12-31. Earlier filings exist only as occasional late amendments, too sparse to describe a market, so they are not shown.
| Quarter | Holders | Value | Shares | New | Added | Trimmed | Options |
|---|---|---|---|---|---|---|---|
| Q3 2026 | 4 | $450.1K | 134,349 | 1 | 0 | 3 | 0.0% |
| Q2 2026 | 35 | $19.2M | 2,270,378 | 6 | 7 | 12 | 6.9% |
| Q1 2026 | 34 | $22.8M | 2,306,473 | 3 | 9 | 9 | 10.1% |
| Q4 2025 | 39 | $45.4M | 2,504,465 | 8 | 14 | 5 | 19.9% |
| Q3 2025 | 41 | $60.9M | 2,125,907 | 14 | 11 | 8 | 32.9% |
| Q2 2025 | 36 | $27.9M | 2,291,892 | 38 | 0 | 1 | 8.9% |
| Q1 2025 | 65 | $43.2M | 61,502,372 | 9 | 14 | 14 | 0.4% |
| Q4 2024 | 70 | $55.5M | 63,076,408 | 8 | 17 | 19 | 5.5% |
| Q3 2024 | 77 | $61.9M | 63,497,572 | 9 | 16 | 26 | 2.9% |
| Q2 2024 | 93 | $50.8M | 69,132,735 | 20 | 23 | 29 | 1.6% |
| Q1 2024 | 98 | $68.4M | 86,770,814 | 18 | 27 | 28 | 1.3% |
| Q4 2023 | 103 | $127.7M | 90,468,058 | 16 | 25 | 41 | 0.8% |
| Q3 2023 | 136 | $268.1M | 109,395,583 | 19 | 51 | 30 | 2.9% |
| Q2 2023 | 140 | $555.2M | 112,328,631 | 36 | 58 | 26 | 3.1% |
| Q1 2023 | 125 | $707.4M | 123,976,659 | 20 | 40 | 35 | 0.6% |
| Q4 2022 | 124 | $591.3M | 105,075,203 | 21 | 37 | 38 | 0.5% |
| Q3 2022 | 117 | $13.2B | 2,054,013,134 | 21 | 46 | 27 | 0.0% |
| Q2 2022 | 120 | $319.3M | 92,389,566 | 18 | 29 | 46 | 0.5% |
| Q1 2022 | 128 | $575.8M | 80,155,485 | 6 | 40 | 49 | 0.9% |
| Q4 2021 | 148 | $1.0B | 118,734,316 | 31 | 41 | 40 | 1.0% |
| Q3 2021 | 131 | $814.0M | 116,314,962 | 27 | 46 | 31 | 0.9% |
| Q2 2021 | 145 | $5.0B | 208,391,920 | 19 | 53 | 46 | 1.0% |
| Q1 2021 | 151 | $7.5B | 363,963,053 | 26 | 56 | 44 | 0.5% |
| Q4 2020 | 153 | $11.1B | 450,456,075 | 49 | 49 | 33 | 0.3% |
| Q3 2020 | 119 | $3.3B | 113,441,540 | 41 | 39 | 29 | 3.1% |
| Q2 2020 | 96 | $445.6M | 92,217,477 | 29 | 40 | 15 | 1.6% |
| Q1 2020 | 75 | $275.7M | 77,264,104 | 10 | 25 | 25 | 0.0% |
| Q4 2019 | 75 | $230.1M | 66,664,017 | 10 | 36 | 15 | 0.1% |
| Q3 2019 | 77 | $259.8M | 64,449,152 | 10 | 33 | 18 | 0.5% |
| Q2 2019 | 87 | $204.4M | 62,149,812 | 26 | 33 | 12 | 2.2% |
| Q1 2019 | 80 | $232.7M | 33,815,396 | 15 | 28 | 17 | 0.1% |
| Q4 2018 | 69 | $144.5M | 31,943,665 | 1 | 0 | 2 | 0.1% |