# SERES THERAPEUTICS INC COM NEW

SERES THERAPEUTICS INC COM NEW is a security (CUSIP 81750R201) tracked across SEC portfolio filings. 32 institutional managers reported $23.9M on Form 13F as of 2026-06-30; 6 registered fund positions totaling $837K via N-PORT as of 2026-05-29.

## Summary

- Issuer: SERES THERAPEUTICS INC
- Class: COM NEW
- CUSIP: 81750R201
- Asset category: EC
- 13F holders: 32
- 13F value: $23.9M
- 13F period: 2026-06-30
- N-PORT fund positions: 6
- N-PORT value: $837K
- N-PORT report: 2026-05-29

## Top institutional holders (Form 13F)

_Showing 15 of 32 managers by value._

| Manager | Location | Value | Shares |
| --- | --- | --- | --- |
| Flagship Pioneering Inc. | Cambridge, MA | $10.3M | 1,155,850 |
| [VANGUARD GROUP INC](https://search.stillhousedata.com/firm/105958) | Valley Forge, PA | $4.8M | 324,214 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | BALA CYNWYD, PA | $2.0M | 105,339 |
| [MARSHALL WACE, LLP](https://search.stillhousedata.com/firm/160885) | LONDON, X0 | $1.2M | 139,539 |
| Vontobel Holding Ltd. | ZURICH, V8 | $970K | 122,975 |
| BlackRock, Inc. | New York, NY | $905K | 102,026 |
| [GEODE CAPITAL MANAGEMENT, LLC](https://search.stillhousedata.com/firm/115504) | BOSTON, MA | $664K | 74,835 |
| AMERICAN CENTURY COMPANIES INC | KANSAS CITY, MO | $553K | 62,316 |
| [CITADEL ADVISORS LLC](https://search.stillhousedata.com/firm/148826) | MIAMI, FL | $528K | — |
| HAP Trading, LLC | NEW YORK, NY | $335K | — |
| STATE STREET CORP | BOSTON, MA | $301K | 33,901 |
| [CHARLES SCHWAB INVESTMENT MANAGEMENT INC](https://search.stillhousedata.com/firm/106753) | SAN FRANCISCO, CA | $281K | 31,630 |
| [Lion Point Capital, LP](https://search.stillhousedata.com/firm/174322) | NEW YORK, NY | $280K | 31,570 |
| MORGAN STANLEY | NEW YORK, NY | $192K | 21,700 |
| [TWO SIGMA INVESTMENTS, LP](https://search.stillhousedata.com/firm/137137) | New York, NY | $167K | 18,794 |

## Top fund holders (N-PORT)

| Fund | Registrant | Value | % of fund |
| --- | --- | --- | --- |
| [VANGUARD EXTENDED MARKET INDEX FUND](https://search.stillhousedata.com/fund/S000002841) | VANGUARD INDEX FUNDS | $620K | 0.08% |
| [VANGUARD INSTITUTIONAL TOTAL STOCK MARKET INDEX FUND](https://search.stillhousedata.com/fund/S000002855) | VANGUARD INSTITUTIONAL INDEX FUNDS | $129K | 0.04% |
| [U.S. MICRO CAP PORTFOLIO](https://search.stillhousedata.com/fund/S000000948) | DFA INVESTMENT DIMENSIONS GROUP INC | $56K | 0.08% |
| [VANGUARD BALANCED INDEX FUND](https://search.stillhousedata.com/fund/S000002560) | VANGUARD VALLEY FORGE FUNDS | $31K | 0.01% |
| Guggenheim Active Allocation Fund | Guggenheim Active Allocation Fund | $146 | 0.00% |
| [Blackstone Alternative Multi-Strategy Fund](https://search.stillhousedata.com/fund/S000045538) | Blackstone Alternative Investment Funds | $-399 | -0.00% |

## More

- [This page as markdown (for LLM agents)](https://search.stillhousedata.com/security/81750R201.md)
- [Search all SEC filings, advisers and people on Adviser Search](https://search.stillhousedata.com/)

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Source: public SEC filing data via Adviser Search (https://search.stillhousedata.com).
Agents: this data is also queryable via MCP tools and read-only SQL — see https://search.stillhousedata.com/llms.txt.