CAMBRIDGE, MA
SERES THERAPEUTICS, INC.MCRB— Latest position per institution from SEC 13F filings
15
Institutional holders
3.14M
Total shares held
28.92M
Estimated value
156.81K
Avg. position size
FLAGSHIP PIONEERING, LLC
CIK 1400240
Shares
1.16M
Value
9.12M
Filed
Jun 30, 2026
VANGUARD GROUP INC
CIK 102909
Shares
324.21K
Value
4.82M
Filed
Dec 31, 2025
VANGUARD CAPITAL MANAGEMENT LLC
CIK 2100119
Shares
287.78K
Value
2.27M
Filed
Jun 30, 2026
MARSHALL WACE, LLP
CIK 1318757
Shares
172.25K
Value
1.36M
Filed
Jun 30, 2026
SUSQUEHANNA INTERNATIONAL GROUP, LLP
CIK 1446194
Shares
133.23K
Value
1.05M
Filed
Jun 30, 2026
HAP TRADING, LLC
CIK 1049854
Shares
125K
Value
334.75K
Filed
Sep 30, 2025
HUDSON BAY CAPITAL MANAGEMENT LP
CIK 1393825
Shares
125K
Value
2.40M
Filed
Sep 30, 2025
VONTOBEL HOLDING LTD.
CIK 1588340
Shares
114.57K
Value
383.80K
Filed
Sep 30, 2026
BLACKROCK, INC.
CIK 2012383
Shares
111K
Value
875.79K
Filed
Jun 30, 2026
J. GOLDMAN & CO LP
CIK 1412741
Shares
88.90K
Value
1.71M
Filed
Sep 30, 2025
GEODE CAPITAL MANAGEMENT, LLC
CIK 1214717
Shares
79.97K
Value
631.30K
Filed
Jun 30, 2026
CAPTION MANAGEMENT, LLC
CIK 1706766
Shares
75K
Value
1.12M
Filed
Dec 31, 2025
TUDOR INVESTMENT CORP ET AL
CIK 923093
Shares
61.98K
Value
43.39K
Filed
Mar 31, 2025
CITADEL ADVISORS LLC
CIK 1423053
Shares
54K
Value
426.09K
Filed
Jun 30, 2026
683 CAPITAL MANAGEMENT, LLC
CIK 1404574
Shares
52.31K
Value
778.43K
Filed
Dec 31, 2025
VANGUARD FIDUCIARY TRUST CO
CIK 933478
Shares
48.69K
Value
384.13K
Filed
Jun 30, 2026
STATE STREET CORP
CIK 93751
Shares
33.90K
Value
267.48K
Filed
Jun 30, 2026
LION POINT CAPITAL, LP
CIK 1643354
Shares
31.57K
Value
249.09K
Filed
Jun 30, 2026
CHARLES SCHWAB INVESTMENT MANAGEMENT INC
CIK 884546
Shares
31.05K
Value
244.98K
Filed
Jun 30, 2026
JANE STREET GROUP, LLC
CIK 1595888
Shares
29.91K
Value
444.99K
Filed
Dec 31, 2025
| # | Institution | CIK | Shares | Est. Value | Period |
|---|---|---|---|---|---|
| 1 | FLAGSHIP PIONEERING, LLC | 1400240 | 1.16M | 9.12M | Jun 30, 2026 |
| 2 | VANGUARD GROUP INC | 102909 | 324.21K | 4.82M | Dec 31, 2025 |
| 3 | VANGUARD CAPITAL MANAGEMENT LLC | 2100119 | 287.78K | 2.27M | Jun 30, 2026 |
| 4 | MARSHALL WACE, LLP | 1318757 | 172.25K | 1.36M | Jun 30, 2026 |
| 5 | SUSQUEHANNA INTERNATIONAL GROUP, LLP | 1446194 | 133.23K | 1.05M | Jun 30, 2026 |
| 6 | HAP TRADING, LLC | 1049854 | 125K | 334.75K | Sep 30, 2025 |
| 7 | HUDSON BAY CAPITAL MANAGEMENT LP | 1393825 | 125K | 2.40M | Sep 30, 2025 |
| 8 | VONTOBEL HOLDING LTD. | 1588340 | 114.57K | 383.80K | Sep 30, 2026 |
| 9 | BLACKROCK, INC. | 2012383 | 111K | 875.79K | Jun 30, 2026 |
| 10 | J. GOLDMAN & CO LP | 1412741 | 88.90K | 1.71M | Sep 30, 2025 |
| 11 | GEODE CAPITAL MANAGEMENT, LLC | 1214717 | 79.97K | 631.30K | Jun 30, 2026 |
| 12 | CAPTION MANAGEMENT, LLC | 1706766 | 75K | 1.12M | Dec 31, 2025 |
| 13 | TUDOR INVESTMENT CORP ET AL | 923093 | 61.98K | 43.39K | Mar 31, 2025 |
| 14 | CITADEL ADVISORS LLC | 1423053 | 54K | 426.09K | Jun 30, 2026 |
| 15 | 683 CAPITAL MANAGEMENT, LLC | 1404574 | 52.31K | 778.43K | Dec 31, 2025 |
| 16 | VANGUARD FIDUCIARY TRUST CO | 933478 | 48.69K | 384.13K | Jun 30, 2026 |
| 17 | STATE STREET CORP | 93751 | 33.90K | 267.48K | Jun 30, 2026 |
| 18 | LION POINT CAPITAL, LP | 1643354 | 31.57K | 249.09K | Jun 30, 2026 |
| 19 | CHARLES SCHWAB INVESTMENT MANAGEMENT INC | 884546 | 31.05K | 244.98K | Jun 30, 2026 |
| 20 | JANE STREET GROUP, LLC | 1595888 | 29.91K | 444.99K | Dec 31, 2025 |
Data sourced from SEC Form 13F institutional holdings reports. Positions reflect the most recent filing per institution.