Stock

Seres Therapeutics, Inc.

MCRB · held by 37 managers

Q1 2026 Q4 2025 Q3 2025 Q2 2025 Q1 2025

Reported value

$36.4M

Holders

+1 new · −0 exited

Holders’ est. mark

−$86.9K

Price effect on 3 books still in the name

Largest holder

$17.2M

Flagship Pioneering, LLC

Notable conviction

Share of each notable manager’s 13F book.

Citadel0.0% · $467.5K
Fidelity0.0% · $25.9K
State Street0.0% · $504.4K
Vanguard0.0% · $4.82M

Holder count by quarter

Q4 2022 Q1 2023 Q2 2023 Q3 2023 Q4 2023 Q1 2024 Q2 2024 Q3 2024 Q4 2024 Q1 2025 Q3 2025 Q4 2025 Q1 2026

Who holds it

Notable only

Investor	Shares	Value	Est. mark	Change
Flagship Pioneering, LLC	1.16M	$17.2M	—	Held
Vanguard	324.2K	$4.82M	—	Held
SUSQUEHANNA INTERNATIONAL GROUP, LLP	179.9K	$2.68M	—	Held
MARSHALL WACE, LLP	120.2K	$1.79M	—	Held
BlackRock, Inc.	103.6K	$1.54M	—	Held
Vontobel Holding Ltd.	103.2K	$1.54M	—	Held
GEODE CAPITAL MANAGEMENT, LLC	86.1K	$1.28M	—	Held
683 Capital Management, LLC	52.3K	$778.4K	—	Held
State Street	33.9K	$504.4K	—	Held
Lion Point Capital, LP	31.6K	$469.8K	—	Held
Citadel	31.4K	$467.5K	—	Held
CHARLES SCHWAB INVESTMENT MANAGEMENT INC	31.4K	$466.8K	—	Held
Schonfeld Strategic Advisors LLC	29.1K	$433K	—	Held
TWO SIGMA INVESTMENTS, LP	25.7K	$383.1K	—	Held
MORGAN STANLEY	25.1K	$373.9K	−$79.9K	Added$21.1K
AMERICAN CENTURY COMPANIES INC	16.3K	$242.1K	—	Held
NORTHERN TRUST CORP	14.8K	$219.7K	—	Held
OMERS ADMINISTRATION Corp	14.4K	$214.3K	—	Held
Invesco Ltd.	14.4K	$213.7K	—	Held
GOLDMAN SACHS GROUP INC	14.3K	$213.4K	—	Held
ExodusPoint Capital Management, LP	12.7K	$189.5K	—	Held
BARCLAYS PLC	7.43K	$110.6K	−$6.14K	Added$83.5K
UBS Group AG	4.23K	$62.9K	—	Held
SBI Securities Co., Ltd.	3.48K	$51.8K	—	Held
Fidelity	1.74K	$25.9K	—	Held
Rachor Investment Advisory Services, LLC	1.48K	$22K	—	Held
SIMPLEX TRADING, LLC	1.23K	$18.3K	—	Held
BNP PARIBAS FINANCIAL MARKETS	773	$11.5K	—	Held
WELLS FARGO & COMPANY/MN	260	$3.87K	—	Held
BANK OF AMERICA CORP /DE/	195	$2.9K	−$850	Cut−$99.9K
Physician Wealth Advisors, Inc.	142	$2.11K	—	Held
HRT FINANCIAL LP	62.9K	$935	—	Held
Sound Income Strategies, LLC	8	$128	—	Held
OSAIC HOLDINGS, INC.	8	$119	—	Held
Allworth Financial LP	4	$60	—	New
Arax Advisory Partners	2	$30	—	Held
ROYAL BANK OF CANADA	9	$0	—	Held

Positions as of Q4 2025. 13F filings arrive up to 45 days after quarter-end and omit shorts. Values are quarter-end marks, as filed. Estimated mark is the price effect on shares still held — not realized P&L or investment advice.