Quantum-Si Incorporated
QSI
125 hedge funds and large institutions have $91.5M invested in Quantum-Si Incorporated in 2025 Q3 according to their latest regulatory filings, with 14 funds opening new positions, 43 increasing their positions, 40 reducing their positions, and 22 closing their positions.
80% more call options, than puts
Call options by funds: $3.33M | Put options by funds: $1.85M
8% more repeat investments, than reductions
Existing positions increased: 43 | Existing positions reduced: 40
3.95% less ownership
Funds ownership: 39.35% → 35.4% (-3.9%)
7% less funds holding
Funds holding: 135 → 125 (-10)
27% less capital invested
Capital invested by funds: $126M → $91.5M (-$34.6M)
36% less first-time investments, than exits
New positions opened: 14 | Existing positions closed: 22
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Jane Street
New York
|
+$1.92M |
| 2 |
Susquehanna International Group
Bala Cynwyd,
Pennsylvania
|
+$1.53M |
| 3 |
Squarepoint
New York
|
+$887K |
| 4 |
BlackRock
New York
|
+$684K |
| 5 |
Geode Capital Management
Boston,
Massachusetts
|
+$433K |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Millennium Management
New York
|
-$1.6M |
| 2 |
Nuveen
Charlotte,
North Carolina
|
-$981K |
| 3 |
Goldman Sachs
New York
|
-$733K |
| 4 |
NAMA
Nikko Asset Management Americas
New York
|
-$584K |
| 5 |
Sumitomo Mitsui Trust Group
Minato-Ku, Tokyo,
Japan
|
-$584K |
QSI Hedge Fund Activity: Q3 2025 in Review
125 of the 7,641 institutional investors tracked by Wall St. Rank reported a position in Quantum-Si Incorporated (QSI) for Q3 2025, worth a combined $91.5M — down 27% from $126M a quarter earlier.
Sellers outnumbered buyers: 22 funds closed out of QSI and 14 opened new positions — a net loss of 8 holders — while 40 trimmed existing stakes and 43 added.
The largest buyer was Jane Street, adding an estimated $1.92M. The largest seller was Millennium Management, cutting an estimated $1.6M.
- 125 institutional investors held Quantum-Si Incorporated (QSI) as of Q3 2025, down from 135 in Q2 2025.
- Funds reported $91.5M of Quantum-Si Incorporated stock for Q3 2025, down 27% quarter-over-quarter.
- 14 funds opened new Quantum-Si Incorporated positions in Q3 2025 and 22 closed out, a net change of -8 holders.
- The largest Quantum-Si Incorporated buyer in Q3 2025 was Jane Street, an estimated $1.92M added.
- The largest Quantum-Si Incorporated seller in Q3 2025 was Millennium Management, an estimated $1.6M sold.
Based on aggregated 13F filings for Q3 2025.