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, Q2 2026
Institutional positions in Quantum-Si Inc as of Jun 30, 2026. 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
- 141
- −14 vs. Q1 2026
- Shares held
- 52.9M
- −10.1M (−16.1%) vs. Q1 2026
- Total value
- $46.8M
- −$2.07M (−4.2%) vs. Q1 2026
- New holders
- 27
- 34 more added
- Sold out
- 41
- 58 more reduced
2 institutions that held it in Q1 2026 haven't filed for Q2 2026 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q1 2026: 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, Q2 2026
Shares, value and share of portfolio for each institution holding Quantum-Si Inc; share changes are against Q1 2026.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| Charles Schwab Investment Management Inc | 84,612 | $74.9K | 0.00% | −372,959−81.5% | Reduced |
| Vanguard Global Advisers, LLC | 84,757 | $75.0K | 0.00% | 00.0% | Unchanged |
| Cerity Partners LLC | 85,347 | $75.5K | 0.00% | +4,697+5.8% | Added |
| AlphaCore Capital LLC | 89,368 | $79.1K | 0.00% | −39,081−30.4% | Reduced |
| HRT Financial LP | 93,647 | $82.0K | 0.00% | +93,647 | New |
| Jones Financial Companies LLLP | 100,483 | $85.8K | 0.00% | −9,417−8.6% | Reduced |
| Group One Trading, L.P. | 107,473 | $95.1K | 0.00% | −176,508−62.2% | Reduced |
| FMR LLC | 123,767 | $109.5K | 0.00% | +91,799+287.2% | Added |
| Shay Capital LLC | 150,922 | $133.6K | 0.01% | 00.0% | Unchanged |
| Mariner, LLC | 157,689 | $139.6K | 0.00% | −42,003−21.0% | Reduced |
| Verdence Capital Advisors LLC | 158,305 | $140.1K | 0.01% | −45,550−22.3% | Reduced |
| Simplex Trading, LLC | 165,293 | $146.3K | 0.00% | +74,762+82.6% | Added |
| XTX Topco Ltd | 177,680 | $157.2K | 0.00% | −211,574−54.4% | Reduced |
| Barclays PLC | 205,690 | $182.0K | 0.00% | +166,553+425.6% | Added |
| Bridgeway Capital Management, LLC | 206,100 | $182.4K | 0.00% | −55,000−21.1% | Reduced |
| IMC-Chicago, LLC | 285,758 | $252.9K | 0.00% | +64,882+29.4% | Added |
| Knollwood Investment Advisory, LLC | 300,000 | $265.5K | 0.02% | 00.0% | Unchanged |
| Davy Global Fund Management Ltd | 321,134 | $284.2K | 0.02% | +29,027+9.9% | Added |
| Morgan Stanley | 323,482 | $286.3K | 0.00% | +193,542+148.9% | Added |
| Aster Capital Management (DIFC) Ltd | 344,510 | $304.9K | 0.06% | +344,510 | New |
| Ieq Capital, LLC | 350,816 | $310.5K | 0.00% | −6,872−1.9% | Reduced |
| BNP Paribas Arbitrage, SA | 398,598 | $352.8K | 0.00% | +360,208+938.3% | Added |
| Invesco Ltd. | 443,929 | $392.9K | 0.00% | +37,239+9.2% | Added |
| Northern Trust Corp | 450,531 | $398.7K | 0.00% | −810,170−64.3% | Reduced |
| Goldman Sachs Group Inc | 476,288 | $421.5K | 0.00% | +32,111+7.2% | Added |
| Vanguard Portfolio Management LLC | 497,098 | $439.9K | 0.00% | −1,023,548−67.3% | Reduced |
| Renaissance Technologies LLC | 553,871 | $490.2K | 0.00% | +435,971+369.8% | Added |
| Fosun International Ltd | 743,935 | $658.4K | 0.15% | 00.0% | Unchanged |
| State Street Corp | 890,741 | $788.3K | 0.00% | −2,879,948−76.4% | Reduced |
| Vanguard Fiduciary Trust Co | 1,116,683 | $988.3K | 0.00% | −569−0.1% | Reduced |
| Susquehanna International Group, LLP | 1,116,750 | $988.3K | 0.00% | −347,818−23.7% | Reduced |
| Jane Street Group, LLC | 2,142,735 | $1.90M | 0.00% | +2,142,735 | New |
| Geode Capital Management, LLC | 2,236,526 | $1.98M | 0.00% | −1,598,595−41.7% | Reduced |
| AQR Capital Management LLC | 2,348,665 | $2.08M | 0.00% | −43,514−1.8% | Reduced |
| UBS Group AG | 2,561,897 | $2.27M | 0.00% | +859,370+50.5% | Added |
| Millennium Management LLC | 3,131,726 | $2.77M | 0.00% | +3,131,726 | New |
| Sumitomo Mitsui Trust Holdings, Inc. | 3,885,230 | $3.44M | 0.00% | −506,436−11.5% | Reduced |
| Nikko Asset Management Americas, Inc. | 3,885,230 | $3.46M | 0.04% | −506,436−11.5% | Reduced |
| BlackRock, Inc. | 5,225,352 | $4.62M | 0.00% | −8,189,597−61.0% | Reduced |
| ARK Investment Management LLCSuperinvestorARK Invest | 7,167,738 | $6.34M | 0.04% | +288,839+4.2% | Added |
| Vanguard Capital Management LLC | 7,578,208 | $6.71M | 0.00% | +556,301+7.9% | Added |
| Alliancebernstein L.P. | 0 | $0 | 0.00% | −272,180−100.0% | Sold out |
| CIBC Bancorp USA Inc. | 0 | $0 | 0.00% | −208,510−100.0% | Sold out |
| Deutsche Bank AG | 0 | $0 | 0.00% | −119,028−100.0% | Sold out |
| Los Angeles Capital Management LLC | 0 | $0 | 0.00% | −116,341−100.0% | Sold out |
| MetLife Investment Management | 0 | $0 | 0.00% | −101,555−100.0% | Sold out |
| Price T Rowe Associates Inc | 0 | $0 | 0.00% | −96,486−100.0% | Sold out |
| Mirae Asset Global ETFs Holdings Ltd. | 0 | $0 | 0.00% | −74,928−100.0% | Sold out |
| Virtu Financial LLC | 0 | $0 | 0.00% | −64,751−100.0% | Sold out |
| Wells Fargo & Company | 0 | $0 | 0.00% | −63,868−100.0% | Sold out |
| Quantbot Technologies LP | 0 | $0 | 0.00% | −58,461−100.0% | Sold out |
| Two Sigma Investments, LP | 0 | $0 | 0.00% | −52,924−100.0% | Sold out |
| Manufacturers Life Insurance Company, The | 0 | $0 | 0.00% | −47,453−100.0% | Sold out |
| Intech Investment Management LLC | 0 | $0 | 0.00% | −46,486−100.0% | Sold out |
| Police & Firemen's Retirement System of New Jersey | 0 | $0 | 0.00% | −46,170−100.0% | Sold out |
| State Board of Administration of Florida Retirement System | 0 | $0 | 0.00% | −41,282−100.0% | Sold out |
| Nine Masts Capital Ltd | 0 | $0 | 0.00% | −41,134−100.0% | Sold out |
| ProShare Advisors LLC | 0 | $0 | 0.00% | −33,239−100.0% | Sold out |
| SEI Investments Co | 0 | $0 | 0.00% | −33,103−100.0% | Sold out |
| Voya Investment Management LLC | 0 | $0 | 0.00% | −27,246−100.0% | Sold out |
| New York State Common Retirement Fund | 0 | $0 | 0.00% | −26,084−100.0% | Sold out |
| Prudential Financial Inc | 0 | $0 | 0.00% | −21,570−100.0% | Sold out |
| Buckingham Strategic Partners | 0 | $0 | 0.00% | −16,473−100.0% | Sold out |
| Ameritas Investment Partners, Inc. | 0 | $0 | 0.00% | −14,401−100.0% | Sold out |
| Xponance, Inc. | 0 | $0 | 0.00% | −13,849−100.0% | Sold out |
| Legal & General Group Plc | 0 | $0 | 0.00% | −12,860−100.0% | Sold out |
| Graham Capital Management, L.P. | 0 | $0 | 0.00% | −12,220−100.0% | Sold out |
| RMB Capital Management, LLC | 0 | $0 | 0.00% | −10,391−100.0% | Sold out |
| Ground Swell Capital, LLC | 0 | $0 | 0.00% | −10,132−100.0% | Sold out |
| California State Teachers Retirement System | 0 | $0 | 0.00% | −8,500−100.0% | Sold out |
| Wolverine Asset Management LLC | 0 | $0 | 0.00% | −6,170−100.0% | Sold out |
| Sterling Capital Management LLC | 0 | $0 | 0.00% | −5,672−100.0% | Sold out |
| Ronald Blue Trust, Inc. | 0 | $0 | 0.00% | −5,000−100.0% | Sold out |
| Hanson & Doremus Investment Management | 0 | $0 | 0.00% | −1,300−100.0% | Sold out |
| MAI Capital Management | 0 | $0 | 0.00% | −1,274−100.0% | Sold out |
| Sound Income Strategies, LLC | 0 | $0 | 0.00% | −1,000−100.0% | Sold out |
| Wealth Preservation Advisors, LLC | 0 | $0 | 0.00% | −549−100.0% | Sold out |
| Walleye Trading LLC | 0 | $0 | 0.00% | −448−100.0% | Sold out |
| Nisa Investment Advisors, LLC | 0 | $0 | 0.00% | −382−100.0% | Sold out |
| Walleye Capital LLC | 0 | $0 | 0.00% | −312−100.0% | Sold out |
| Root Financial Partners, LLC | 0 | $0 | 0.00% | −292−100.0% | Sold out |
| Kilter Group LLC | 0 | $0 | 0.00% | −4−100.0% | Sold out |
| CWM, LLC | – | – | – | – | Not filed |
| Sunbelt Securities, Inc. | – | – | – | – | Not filed |