Seres Therapeutics
MCRB
35 hedge funds and large institutions have $17.9M invested in Seres Therapeutics in 2026 Q2 according to their latest regulatory filings, with 7 funds opening new positions, 7 increasing their positions, 12 reducing their positions, and 5 closing their positions.
40% more first-time investments, than exits
New positions opened: 7 | Existing positions closed: 5
6% more funds holding
Funds holding: 33 → 35 (+2)
0% more funds holding in top 10
Funds holding in top 10: 1 → 1 (0)
0.62% less ownership
Funds ownership: 24.06% → 23.44% (-0.62%)
12% less capital invested
Capital invested by funds: $20.5M → $17.9M (-$2.55M)
42% less repeat investments, than reductions
Existing positions increased: 7 | Existing positions reduced: 12
74% less call options, than puts
Call options by funds: $274K | Put options by funds: $1.06M
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Marshall Wace
London,
United Kingdom
|
+$249K |
| 2 |
XT
XTX Topco
George Town,
Cayman Islands
|
+$158K |
| 3 |
Goldman Sachs
New York
|
+$116K |
| 4 |
Citadel Advisors
Miami,
Florida
|
+$80K |
| 5 |
Vanguard Fiduciary Trust
Malvern,
Pennsylvania
|
+$68.8K |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Susquehanna International Group
Bala Cynwyd,
Pennsylvania
|
-$358K |
| 2 |
American Century Companies
Kansas City,
Missouri
|
-$259K |
| 3 |
Two Sigma Investments
New York
|
-$167K |
| 4 |
Vontobel Holding
Zurich,
Switzerland
|
-$118K |
| 5 |
Morgan Stanley
New York
|
-$72.8K |
MCRB Hedge Fund Activity: Q2 2026 in Review
35 of the 8,337 institutional investors tracked by Wall St. Rank reported a position in Seres Therapeutics (MCRB) for Q2 2026, worth a combined $17.9M — down 12% from $20.5M a quarter earlier.
Buyers outnumbered sellers: 7 funds opened new MCRB positions and 5 closed out — a net gain of 2 holders — while 7 added to existing stakes and 12 trimmed.
The largest buyer was Marshall Wace, adding an estimated $249K. The largest seller was Susquehanna International Group, cutting an estimated $358K.
- 35 institutional investors held Seres Therapeutics (MCRB) as of Q2 2026, up from 33 in Q1 2026.
- Funds reported $17.9M of Seres Therapeutics stock for Q2 2026, down 12% quarter-over-quarter.
- 7 funds opened new Seres Therapeutics positions in Q2 2026 and 5 closed out, a net change of +2 holders.
- The largest Seres Therapeutics buyer in Q2 2026 was Marshall Wace, an estimated $249K added.
- The largest Seres Therapeutics seller in Q2 2026 was Susquehanna International Group, an estimated $358K sold.
Based on aggregated 13F filings for Q2 2026.