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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
John S. VieceliChief Product Officer2025-12-2221,927$1.28
$27.98kSell
Jeffrey Alan HawkinsPresident CEO2025-12-2223,707$1.28
$30.25kSell
Jeffry R. KeyesChief Financial Officer2025-12-228,627$1.28
$11.01kSell
Christian LapointeGC Corp. Secretary2025-12-2211,951$1.28
$15.25kSell
Jonathan M. RothbergDirector2025-10-1626,095$3.07
$80.11kSell
Jeffry R. KeyesChief Financial Officer2025-09-233,873$1.64
$6.33kSell
John S. VieceliChief Product Officer2025-09-239,843$1.64
$16.09kSell
Todd C. BennettChief Commercial Officer2025-09-2318,482$1.64
$30.22kSell
Jeffrey Alan HawkinsPresident CEO2025-09-2310,643$1.64
$17.40kSell
Christian LapointeGC Corp. Secretary2025-09-235,364$1.64
$8.77kSell

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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. Rothberg23.46%50,765,194$48.13MInsider
4c Holdings I LLC8.29%17,943,750$17.01MInsider
Blackrock Inc6.03%13,054,057$12.38MInstitution
2012 Jmr Trust Common LLC5.77%12,480,108$11.83MInsider
Vanguard Group Inc4.44%9,607,022$9.11MInstitution
James B. Tananbaum3.89%8,424,317$7.99MInsider
Ark Investment Management LLC3.25%7,021,571$6.66MInstitution
Sumitomo Mitsui Trust Group Inc2.17%4,690,720$4.45MInstitution
Amova Asset Management Americas Inc2.17%4,690,720$4.45MInstitution
Geode Capital Management LLC1.90%4,114,375$3.90MInstitution

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QSI vs Biotech Stocks

TickerInst. %Insider %Net Insider (L12M)Net Insider (L3M)
QSI31.18%47.33%Net SellingNet Selling
NKTX60.99%39.01%Net SellingNet Selling
ABOS58.87%18.38%Net SellingNet Selling
GALT13.21%86.79%Net SellingNet Selling
CGEN13.32%0.00%
View Top Biotech Stocks

Quantum Si Stock Ownership FAQ

Who owns Quantum Si?

Quantum Si (NASDAQ: QSI) is owned by 31.18% institutional shareholders, 47.33% Quantum Si insiders, and 21.49% retail investors. Jonathan M. Rothberg is the largest individual Quantum Si shareholder, owning 50.77M shares representing 23.46% of the company. Jonathan M. Rothberg's Quantum Si shares are currently valued at $46.20M.

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