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

Insider buying vs selling

Have Quantum Si Inc insiders been buying or selling?

Buy
Sell
NameRoleDateSharesPriceValue
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
Jeffry R. KeyesChief Financial Officer2025-09-233,873$1.64
$6.33kSell
Christian LapointeGC Corp. Secretary2025-09-235,364$1.64
$8.77kSell
Todd C. BennettChief Commercial Officer2025-09-2218,482$1.68
$31.11kSell
Jeffrey Alan HawkinsPresident CEO2025-09-2210,643$1.68
$17.91kSell
Christian LapointeGC Corp. Secretary2025-09-225,364$1.68
$9.03kSell
Jeffry R. KeyesChief Financial Officer2025-09-223,873$1.68
$6.52kSell
John S. VieceliChief Product Officer2025-09-229,843$1.68
$16.57kSell

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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. Rothberg23.74%48,067,448$126.42MInsider
4c Holdings I LLC8.86%17,943,750$47.19MInsider
2012 Jmr Trust Common LLC6.16%12,480,108$32.82MInsider
Blackrock Inc5.36%10,848,142$28.53MInstitution
Vanguard Group Inc4.28%8,669,661$22.80MInstitution
James B. Tananbaum4.16%8,424,317$22.16MInsider
Ark Investment Management LLC3.93%7,960,736$20.94MInstitution
Sumitomo Mitsui Trust Group Inc2.78%5,621,303$14.78MInstitution
Nikko Asset Management Americas Inc2.78%5,621,303$14.78MInstitution
Millennium Management LLC1.87%3,779,259$9.94MInstitution

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QSI vs Biotech Stocks

TickerInst. %Insider %Net Insider (L12M)Net Insider (L3M)
QSI31.75%49.28%Net SellingNet Selling
CGEM57.08%42.92%Net BuyingNet Buying
MNPR14.23%85.77%Net SellingNet Selling
VSTM51.47%48.53%Net SellingNet Selling
RIGL35.91%64.09%Net Selling

Quantum Si Stock Ownership FAQ

Who owns Quantum Si?

Quantum Si (NASDAQ: QSI) is owned by 31.75% institutional shareholders, 49.28% Quantum Si insiders, and 18.97% retail investors. Jonathan M. Rothberg is the largest individual Quantum Si shareholder, owning 48.07M shares representing 23.74% of the company. Jonathan M. Rothberg's Quantum Si shares are currently valued at $122.09M.

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