Quantum-Si Inc
QSI- Exchange
- Nasdaq
- Industry
- Measuring & Controlling Devices, NEC
- SEC CIK
- 0001816431
In the last 90 days, Quantum-Si Inc insiders filed 0 open-market purchases and 3 sales; 141 institutions reported holding it in 13F filings for Q2 2026, worth $46.8M in total; ARK Invest is the only superinvestor holding it.
13F holders, Q3 2023
Institutional positions in Quantum-Si Inc as of Sep 30, 2023. Investment managers with $100 million or more in US stocks report their long positions on Form 13F within 45 days after each quarter ends. How 13F works
- Institutional holders
- 96
- +5 vs. Q2 2023
- Shares held
- 54.5M
- +10.7M (+24.4%) vs. Q2 2023
- Total value
- $90.5M
- +$12.0M (+15.3%) vs. Q2 2023
- New holders
- 20
- 32 more added
- Sold out
- 15
- 16 more reduced
Compare with Q2 2023: new holders, sold out and not filed yet
Holders and value by quarter
Institutions reporting QSI on Form 13F each quarter since Q1 2021, and the total value they reported. Values are as of each quarter end, so they also move with the share price.
| Quarter | Holders | Value |
|---|---|---|
| Q2 2026 | 141 | $46.8M |
| Q1 2026 | 157 | $49.0M |
| Q4 2025 | 135 | $74.3M |
| Q3 2025 | 125 | $91.3M |
| Q2 2025 | 135 | $126.2M |
| Q1 2025 | 137 | $69.3M |
| Q4 2024 | 121 | $144.8M |
| Q3 2024 | 107 | $45.9M |
| Q2 2024 | 99 | $56.1M |
| Q1 2024 | 95 | $104.1M |
| Q4 2023 | 91 | $113.6M |
| Q3 2023 | 96 | $90.5M |
| Q2 2023 | 91 | $78.5M |
| Q1 2023 | 100 | $76.5M |
| Q4 2022 | 105 | $90.9M |
| Q3 2022 | 102 | $130.8M |
| Q2 2022 | 102 | $139.6M |
| Q1 2022 | 92 | $215.0M |
| Q4 2021 | 93 | $370.6M |
| Q3 2021 | 73 | $372.4M |
| Q2 2021 | 72 | $534.9M |
| Q1 2021 | 0 | $0 |
Institutions, Q3 2023
Shares, value and share of portfolio for each institution holding Quantum-Si Inc; share changes are against Q2 2023.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| Clearline Capital LP | 0 | $0 | 0.00% | −211,900−100.0% | Sold out |
| D.A. Davidson & Co. | 0 | $0 | 0.00% | −125,000−100.0% | Sold out |
| Citadel Advisors LLC | 0 | $0 | 0.00% | −107,111−100.0% | Sold out |
| Westchester Capital Management, LLC | 0 | $0 | 0.00% | −64,964−100.0% | Sold out |
| Man Group plc | 0 | $0 | 0.00% | −44,653−100.0% | Sold out |
| XTX Topco Ltd | 0 | $0 | 0.00% | −44,168−100.0% | Sold out |
| Prelude Capital Management, LLC | 0 | $0 | 0.00% | −20,934−100.0% | Sold out |
| Mutual Advisors, LLC | 0 | $0 | 0.00% | −14,358−100.0% | Sold out |
| D. E. Shaw & Co., Inc. | 0 | $0 | 0.00% | −13,919−100.0% | Sold out |
| Simplex Trading, LLC | 0 | $0 | 0.00% | −9,322−100.0% | Sold out |
| Group One Trading, L.P. | 0 | $0 | 0.00% | −3,154−100.0% | Sold out |