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, Q4 2025
Institutional positions in Quantum-Si Inc as of Dec 31, 2025. 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
- 135
- +13 vs. Q3 2025
- Shares held
- 67.5M
- +2.92M (+4.5%) vs. Q3 2025
- Total value
- $74.3M
- −$17.0M (−18.6%) vs. Q3 2025
- New holders
- 32
- 38 more added
- Sold out
- 19
- 37 more reduced
3 institutions that held it in Q3 2025 haven't filed for Q4 2025 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q3 2025: 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, Q4 2025
Shares, value and share of portfolio for each institution holding Quantum-Si Inc; share changes are against Q3 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| Los Angeles Capital Management LLC | 93,010 | $188.8K | 0.00% | +93,010 | New |
| Wells Fargo & Company | 176,132 | $193.7K | 0.00% | +40,182+29.6% | Added |
| Verdence Capital Advisors LLC | 187,805 | $206.6K | 0.01% | +23,975+14.6% | Added |
| Millennium Management LLC | 191,791 | $211.0K | 0.00% | −2,478,168−92.8% | Reduced |
| Rhumbline Advisers | 193,595 | $212.9K | 0.00% | −26,370−12.0% | Reduced |
| Virtu Financial LLC | 238,379 | $262.0K | 0.01% | +238,379 | New |
| Group One Trading, L.P. | 245,801 | $270.4K | 0.01% | −131,973−34.9% | Reduced |
| Davy Global Fund Management Ltd | 253,895 | $279.3K | 0.02% | +64,721+34.2% | Added |
| Bank of America Corp | 258,445 | $284.3K | 0.00% | −89,562−25.7% | Reduced |
| Bridgeway Capital Management, LLC | 261,100 | $287.2K | 0.01% | 00.0% | Unchanged |
| Barclays PLC | 269,415 | $296.4K | 0.00% | +48,205+21.8% | Added |
| Alliancebernstein L.P. | 272,180 | $299.4K | 0.00% | 00.0% | Unchanged |
| Quadrature Capital Ltd | 276,889 | $304.6K | 0.00% | +276,889 | New |
| Knollwood Investment Advisory, LLC | 300,000 | $330.0K | 0.03% | 00.0% | Unchanged |
| Goldman Sachs Group Inc | 386,824 | $425.5K | 0.00% | −327−0.1% | Reduced |
| Morgan Stanley | 399,994 | $440.0K | 0.00% | +128,994+47.6% | Added |
| Invesco Ltd. | 402,821 | $443.1K | 0.00% | +107,093+36.2% | Added |
| Bank of New York Mellon Corp | 406,291 | $446.9K | 0.00% | +11,386+2.9% | Added |
| Nuveen, LLC | 447,519 | $492.3K | 0.00% | 00.0% | Unchanged |
| XTX Topco Ltd | 461,982 | $508.2K | 0.01% | +311,450+206.9% | Added |
| Charles Schwab Investment Management Inc | 468,174 | $515.0K | 0.00% | +860.0% | Added |
| Fosun International Ltd | 743,935 | $818.3K | 0.19% | 00.0% | Unchanged |
| Jane Street Group, LLC | 1,104,033 | $1.21M | 0.00% | −505,990−31.4% | Reduced |
| Two Sigma Investments, LP | 1,384,181 | $1.52M | 0.00% | +868,329+168.3% | Added |
| UBS Group AG | 1,449,512 | $1.59M | 0.00% | +944,653+187.1% | Added |
| Northern Trust Corp | 2,207,936 | $2.43M | 0.00% | −115,106−5.0% | Reduced |
| Susquehanna International Group, LLP | 2,327,785 | $2.56M | 0.00% | +286,690+14.0% | Added |
| Citadel Advisors LLC | 2,676,097 | $2.94M | 0.00% | +2,269,050+557.4% | Added |
| State Street Corp | 3,562,721 | $3.92M | 0.00% | +745,231+26.5% | Added |
| Geode Capital Management, LLC | 4,114,375 | $4.53M | 0.00% | +367,206+9.8% | Added |
| Nikko Asset Management Americas, Inc. | 4,690,720 | $5.11M | 0.06% | −526,779−10.1% | Reduced |
| Sumitomo Mitsui Trust Holdings, Inc. | 4,690,720 | $5.16M | 0.00% | −526,779−10.1% | Reduced |
| ARK Investment Management LLCSuperinvestorARK Invest | 7,021,571 | $7.72M | 0.05% | −602,471−7.9% | Reduced |
| Vanguard Group Inc | 9,607,022 | $10.6M | 0.00% | +892,515+10.2% | Added |
| BlackRock, Inc. | 13,054,057 | $14.4M | 0.00% | +1,732,384+15.3% | Added |
| Squarepoint Ops LLC | 0 | $0 | 0.00% | −613,475−100.0% | Sold out |
| IMC-Chicago, LLC | 0 | $0 | 0.00% | −185,117−100.0% | Sold out |
| Pathstone Holdings, LLC | 0 | $0 | 0.00% | −183,934−100.0% | Sold out |
| Engineers Gate Manager LP | 0 | $0 | 0.00% | −41,451−100.0% | Sold out |
| Elite Life Management LLC | 0 | $0 | 0.00% | −20,611−100.0% | Sold out |
| Mercer Global Advisors Inc | 0 | $0 | 0.00% | −26,989−100.0% | Sold out |
| DLK Investment Management, LLC | 0 | $0 | 0.00% | −19,750−100.0% | Sold out |
| Jump Financial, LLC | 0 | $0 | 0.00% | −15,100−100.0% | Sold out |
| CIBC World Markets Inc. | 0 | $0 | 0.00% | −14,000−100.0% | Sold out |
| Prudential Financial Inc | 0 | $0 | 0.00% | −12,850−100.0% | Sold out |
| Principal Financial Group Inc | 0 | $0 | 0.00% | −11,156−100.0% | Sold out |
| Mark Sheptoff Financial Planning, LLC | 0 | $0 | 0.00% | −10,500−100.0% | Sold out |
| TriaGen Wealth Management LLC | 0 | $0 | 0.00% | −10,000−100.0% | Sold out |
| Principal Securities, Inc. | 0 | $0 | 0.00% | −6,641−100.0% | Sold out |
| Belvedere Trading LLC | 0 | $0 | 0.00% | −1,390−100.0% | Sold out |
| Bangor Savings Bank | 0 | $0 | 0.00% | −400−100.0% | Sold out |
| Atlantic Union Bankshares Corp | 0 | $0 | 0.00% | −251−100.0% | Sold out |
| SRS Capital Advisors, Inc. | 0 | $0 | 0.00% | −104−100.0% | Sold out |
| Summit Wealth Group LLC | 0 | $0 | 0.00% | −2,330−100.0% | Sold out |
| Wolverine Trading, LLC | – | – | – | – | Not filed |
| CIBC Bancorp USA Inc. | – | – | – | – | Not filed |
| FSA Wealth Management LLC | – | – | – | – | Not filed |