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NASDAQ: QSI
Quantum Si Inc Stock Ownership - Who owns Quantum Si?

OverviewForecastEarningsRevenueDividendOwnership

Insider buying vs selling

Have Quantum Si Inc insiders been buying or selling?

Buy
Sell
NameRoleDateSharesPriceValue
Jeffry R. KeyesChief Financial Officer2026-04-2137,381$1.00
$37.19kSell
Jeffrey Alan HawkinsPresident CEO2026-04-2183,712$1.00
$83.29kSell
Jeffrey Alan HawkinsPresident CEO2026-04-2083,712$1.01
$84.21kSell
Jeffry R. KeyesChief Financial Officer2026-04-2037,382$1.01
$37.61kSell
John S. VieceliChief Product Officer2026-03-2311,239$0.83
$9.29kSell
Jeffrey Alan HawkinsPresident CEO2026-03-2312,149$0.83
$10.05kSell
Jeffry R. KeyesChief Financial Officer2026-03-234,422$0.83
$3.66kSell
Christian LapointeGC Corp. Secretary2026-03-236,110$0.83
$5.05kSell
Jeffrey Alan HawkinsPresident CEO2026-03-2011,628$0.85
$9.86kSell
Jeffry R. KeyesChief Financial Officer2026-03-204,233$0.85
$3.59kSell

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Net Insider Buy/Sell (L12M) Ownership

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QSI Shareholders

What type of owners hold Quantum Si Inc stock?

Institutional
Insider
Retail
NameHoldSharesValueType
Jonathan M. Rothberg23.31%50,765,194$60.41MInsider
4c Holdings I LLC8.24%17,943,750$21.35MInsider
Blackrock Inc6.16%13,414,949$15.96MInstitution
2012 Jmr Trust Common LLC5.73%12,480,108$14.85MInsider
James B. Tananbaum3.87%8,424,317$10.02MInsider
Vanguard Capital Management LLC3.22%7,021,907$8.36MInstitution
Ark Investment Management LLC3.16%6,878,899$8.19MInstitution
Sumitomo Mitsui Trust Group Inc2.02%4,391,666$5.23MInstitution
Amova Asset Management Americas Inc2.02%4,391,666$5.23MInstitution
Geode Capital Management LLC1.76%3,835,121$4.56MInstitution

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QSI vs Biotech Stocks

TickerInst. %Insider %Net Insider (L12M)Net Insider (L3M)
QSI28.97%48.37%Net BuyingNet Buying
NVCT17.04%42.11%Net Buying
TARA58.74%41.26%Net SellingNet Selling
CNTX86.17%1.43%Net Buying
ALXO70.06%10.89%Net BuyingNet Selling
View Top Biotech Stocks

Quantum Si Stock Ownership FAQ

Who owns Quantum Si?

Quantum Si (NASDAQ: QSI) is owned by 28.97% institutional shareholders, 48.37% Quantum Si insiders, and 22.66% retail investors. Jonathan M. Rothberg is the largest individual Quantum Si shareholder, owning 50.77M shares representing 23.31% of the company. Jonathan M. Rothberg's Quantum Si shares are currently valued at $60.41M.

If you're new to stock investing, here's how to buy Quantum Si stock.
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