QUANTUM-SI INC (QSI) Institutional Shareholders
QUANTUM-SI INC (QSI) is currently reported in institutional portfolios tracked by InsiderSet based on the latest available SEC Form 13F filings for the quarter ended June 30, 2026. The institutional investors covered on this page collectively reported approximately $48.77M in QSI holdings during the latest filing period.
Blackrock, Inc. is currently the largest disclosed institutional shareholder of QSI tracked by InsiderSet, reporting ownership valued at approximately $10.38M in its March 31, 2026 SEC Form 13F filing. Based on current market prices and the latest disclosed share count, the position is now estimated to be worth approximately $10.01M, representing an estimated loss of -3.62% since the filing period.
The top 10 institutional shareholders tracked on this page collectively account for approximately 78% of the total disclosed QSI value among the investors covered in this analysis. Major shareholders include Blackrock, Inc., Vanguard Capital Management Llc, ARK Invest, and several other long-term asset managers with concentrated positions in QUANTUM-SI INC (QSI).
This page ranks the largest institutional QSI shareholders using publicly disclosed SEC Form 13F data, including reported values, estimated current holding values, portfolio allocation percentages, ownership concentration metrics, and historical holding changes across major hedge funds and investment firms.
Institutional Holders
149
Total Reported Value
$48.77M
Largest Holder
Blackrock, Inc.
Largest Position
$10.38M
Insider Transactions (90d)
8
Latest Filing Quarter
Q2 2026
New Institutional Positions
175
Funds Exiting Positions
0
| Name | Investor/Manager | Portfolio % | Quantity | Reported Balance | Current Estimated Value | Gain/loss Since Filing | Estimated Portfolio Performance |
|---|---|---|---|---|---|---|---|
| Blackrock, Inc. | 0.00% | 13,414,949 | $10,383,169 | $10,007,552 | -$375,617 | -3.62% | |
| Vanguard Capital Management Llc | 0.00% | 7,021,907 | $5,434,956 | $5,238,343 | -$196,613 | -3.62% | |
| ARK Invest | Cathie Wood | 0.04% | 6,878,899 | $5,324,268 | $5,131,659 | -$192,609 | -3.62% |
| Sumitomo Mitsui Trust Group, Inc. | 0.00% | 3,885,230 | $3,438,429 | $2,898,382 | -$540,047 | -15.71% | |
| Amova Asset Management Americas, Inc. | 0.05% | 4,391,666 | $3,425,499 | $3,276,183 | -$149,316 | -4.36% | |
| Geode Capital Management, Llc | 0.00% | 3,835,121 | $2,969,295 | $2,861,000 | -$108,295 | -3.65% | |
| State Street Corp | 0.00% | 3,770,689 | $2,918,513 | $2,812,934 | -$105,579 | -3.62% | |
| Aqr Capital Management Llc | 0.00% | 2,392,179 | $1,851,547 | $1,784,566 | -$66,981 | -3.62% | |
| Ubs Group Ag | 0.00% | 1,702,527 | $1,317,757 | $1,270,085 | -$47,672 | -3.62% | |
| Vanguard Portfolio Management Llc | 0.00% | 1,520,646 | $1,176,980 | $1,134,402 | -$42,578 | -3.62% | |
| Susquehanna International Group, Llp | 0.00% | 1,464,568 | $1,133,576 | $1,092,568 | -$41,008 | -3.62% | |
| Northern Trust Corp | 0.00% | 1,260,701 | $975,783 | $940,483 | -$35,300 | -3.62% | |
| Vanguard Fiduciary Trust Co | 0.00% | 1,117,252 | $864,753 | $833,470 | -$31,283 | -3.62% | |
| Fosun International Ltd | 0.14% | 743,935 | $575,806 | $554,976 | -$20,830 | -3.62% | |
| Charles Schwab Investment Management Inc | 0.00% | 457,571 | $354,160 | $341,348 | -$12,812 | -3.62% | |
| Nuveen, Llc | 0.00% | 451,367 | $349,358 | $336,720 | -$12,638 | -3.62% | |
| Goldman Sachs Group Inc | 0.00% | 444,177 | $343,793 | $331,356 | -$12,437 | -3.62% | |
| Invesco Ltd. | 0.00% | 406,690 | $314,778 | $303,391 | -$11,387 | -3.62% | |
| Xtx Topco Ltd | 0.01% | 389,254 | $301,283 | $290,383 | -$10,900 | -3.62% | |
| Alliancebernstein L.P. | 0.00% | 272,180 | $299,398 | $203,046 | -$96,352 | -32.18% | |
| Bank Of New York Mellon Corp | 0.00% | 383,088 | $296,510 | $285,784 | -$10,726 | -3.62% | |
| Iq Eq Fund Management (Ireland) Ltd | 0.02% | 321,134 | $284,204 | $239,566 | -$44,638 | -15.71% | |
| Ieq Capital, Llc | 0.00% | 357,688 | $276,850 | $266,835 | -$10,015 | -3.62% | |
| Knollwood Investment Advisory, Llc | 0.02% | 300,000 | $232,200 | $223,800 | -$8,400 | -3.62% | |
| Group One Trading Llc | 0.01% | 283,981 | $219,801 | $211,850 | -$7,951 | -3.62% | |
| Bridgeway Capital Management, Llc | 0.00% | 261,100 | $202,091 | $194,781 | -$7,310 | -3.62% | |
| Imc-Chicago, Llc | 0.00% | 220,876 | $170,958 | $164,773 | -$6,185 | -3.62% | |
| Cibc Bancorp Usa Inc. | 0.00% | 208,510 | $161,387 | $155,548 | -$5,839 | -3.62% | |
| Mariner, Llc | 0.00% | 199,692 | $154,546 | $148,970 | -$5,576 | -3.61% | |
| Rhumbline Advisers | 0.00% | 193,068 | $149,425 | $144,029 | -$5,396 | -3.61% | |
| Verdence Capital Advisors Llc | 0.01% | 158,305 | $140,100 | $118,096 | -$22,004 | -15.71% | |
| Bank Of America Corp | 0.00% | 161,987 | $125,377 | $120,842 | -$4,535 | -3.62% | |
| Shay Capital Llc | 0.02% | 150,922 | $116,814 | $112,588 | -$4,226 | -3.62% | |
| Morgan Stanley | 0.00% | 129,940 | $100,574 | $96,935 | -$3,639 | -3.62% | |
| Alphacore Capital Llc | 0.00% | 128,449 | $99,420 | $95,823 | -$3,597 | -3.62% | |
| Cwm, Llc | 0.00% | 126,632 | $98,013 | $94,467 | -$3,546 | -3.62% | |
| Deutsche Bank Ag\ | 0.00% | 119,028 | $91,652 | $88,795 | -$2,857 | -3.12% | |
| Renaissance Technologies LLC | Jim Simons | 0.00% | 117,900 | $91,255 | $87,953 | -$3,302 | -3.62% |
| Los Angeles Capital Management Llc | 0.00% | 116,341 | $90,047 | $86,790 | -$3,257 | -3.62% | |
| Jones Financial Companies Lllp | 0.00% | 109,900 | $83,964 | $81,985 | -$1,979 | -2.36% | |
| Metlife Investment Management, Llc | 0.00% | 101,555 | $78,604 | $75,760 | -$2,844 | -3.62% | |
| Simplex Trading, Llc | 0.00% | 90,531 | $70,070 | $67,536 | -$2,534 | -3.62% | |
| Y-Intercept (Hong Kong) Ltd | 0.00% | 79,089 | $69,994 | $59,000 | -$10,994 | -15.71% | |
| Vanguard Global Advisers, Llc | 0.00% | 84,757 | $65,602 | $63,229 | -$2,373 | -3.62% | |
| Cerity Partners Llc | 0.00% | 80,650 | $62,423 | $60,165 | -$2,258 | -3.62% | |
| Mirae Asset Global Etfs Holdings Ltd. | 0.00% | 74,928 | $57,994 | $55,896 | -$2,098 | -3.62% | |
| Captrust Financial Advisors | 0.00% | 69,036 | $53,427 | $51,501 | -$1,926 | -3.61% | |
| Wells Fargo & Company/Mn | 0.00% | 63,868 | $49,434 | $47,646 | -$1,788 | -3.62% | |
| Quantbot Technologies Lp | 0.00% | 58,461 | $45,249 | $43,612 | -$1,637 | -3.62% | |
| Wealth Enhancement Advisory Services, Llc | 0.00% | 63,435 | $45,198 | $47,323 | +$2,125 | +4.70% |
Frequently asked questions about QSI
Who owns the most QSI stock?
The largest holders of QSI are typically major institutional investors such as asset managers and hedge funds reporting on Form 13F. The table above ranks tracked superinvestors by reported position size using the latest available filings for QUANTUM-SI INC (QSI).
Is QSI widely held by superinvestors?
Many widely followed stocks like QSI appear across numerous superinvestor portfolios because of liquidity, index inclusion, and fundamentals. The holder count and table above show how broadly QSI is represented among the institutional managers we track.
What do “Current Estimated Value”, “Gain/loss Since Filing”, and “Estimated Portfolio Performance” mean?
Current Estimated Value is reported share quantity from the latest 13F times our most recent split-adjusted U.S. session close. Gain/loss Since Filing is that estimate minus the reported 13F dollar value; Estimated Portfolio Performance is that difference as a percent of the reported value. Green means the estimate is above the filing value; red means below (not purchase cost). If many filers share the same implied filing price per share, the performance % may match across rows. These are not official fund marks or live quotes.