Welcome to our dedicated page for Quantum-Si SEC filings (Ticker: QSI), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
Our SEC filing database is enhanced with expert analysis from Rhea-AI, providing insights into the potential impact of each filing on Quantum-Si's stock performance. Each filing includes a concise AI-generated summary, sentiment and impact scores, and end-of-day stock performance data showing the actual market reaction. Navigate easily through different filing types including 10-K annual reports, 10-Q quarterly reports, 8-K current reports, proxy statements (DEF 14A), and Form 4 insider trading disclosures.
Designed for fundamental investors and regulatory compliance professionals, our page simplifies access to critical SEC filings. By combining real-time SEC filing updates, Rhea-AI's analytical insights, and historical stock performance data, we provide comprehensive visibility into Quantum-Si's regulatory disclosures and financial reporting.
Quantum-Si Inc (QSI) is the subject of this amended Schedule 13D, which updates the beneficial ownership and trading plans of its founder, Jonathan M. Rothberg, Ph.D. Rothberg is reported to beneficially own 14,376,415 shares of Class A common stock, representing 7.20% of the 198,946,412 Class A shares outstanding as of August 11, 2026. He also beneficially owns 19,937,500 shares of Class B common stock, representing 100% of the Class B shares outstanding.
The Class A holdings include shares held directly by Rothberg, options exercisable within 60 days, and shares held by entities owned by trusts for his children, as well as shares held by his spouse and by 23rd Century Capital LLC. In connection with estate planning, entities owned by these trusts have entered into a Rule 10b5-1 trading plan under which sales of up to 8,947,746 Class A shares may occur between January 15, 2027 and January 15, 2028, subject to minimum price parameters, with no assurance that any sales will occur.
Quantum-Si Incorporated reported continued operating losses while revenue declined sharply as customers deferred purchases ahead of the planned launch of its next-generation Proteus platform. Total revenue was $344 thousand for the quarter and $602 thousand for the first half of 2026, down 41.8% and 58.0% from 2025, driven by lower instrument and consumables sales.
The company recorded a net loss of $23.5 million for the quarter and $45.2 million year-to-date, modestly improved from prior-year periods as selling, general and administrative expenses fell 17.5% for the first half. Research and development spending increased to $30.3 million year-to-date as work on Proteus accelerated. Cash, cash equivalents and marketable securities totaled $169.9 million as of June 30, 2026, and management expects these resources to fund operations for at least 12 months. Subsequent events include a Nasdaq minimum bid price deficiency notice and a restructuring program reducing the workforce by about 20%, with expected cash charges of $2.6 million in the second half of 2026.
Quantum-Si Incorporated reported second-quarter 2026 revenue of $344 thousand, down from $591 thousand a year earlier, as it transitions from its Platinum platform to the anticipated Proteus platform. Six-month 2026 revenue was $602 thousand versus $1.4 million in the prior-year period.
Gross profit for the quarter was $172 thousand with a 50% gross margin. Total operating expenses declined to $25.8 million from $30.5 million, and net loss improved to $23.5 million from $28.8 million. Adjusted EBITDA for the quarter was negative $21.2 million. The company ended June 30, 2026 with $169.9 million in cash, cash equivalents and marketable securities and expects this to fund operations into the fourth quarter of 2028.
Quantum-Si updated its anticipated commercial launch of Proteus to Q2 2027 to allow an additional integrated instrument design cycle, and announced a 20% workforce reduction expected to generate about $12 million in annualized operating expense savings. Management reiterated 2026 guidance of approximately $1.0 million in revenue, adjusted total operating expenses of $98.0 million or less, and total cash usage of $93.0 million or less, and highlighted an estimated $4 billion annual non-human proteomics market opportunity.
BlackRock, Inc. filed an amended Schedule 13G reporting its beneficial ownership of Class A stock of Quantum-Si Inc. BlackRock reported beneficial ownership of 4,598,208 Class A shares, representing 2.3% of the class. All of these shares are reported with sole voting power and sole dispositive power, with no shared voting or dispositive power. Various underlying clients and funds have economic interests in these shares, but no single such person's interest exceeds five percent of Quantum-Si’s outstanding common shares.
Quantum-Si Incorporated reported receiving a Nasdaq Listing Qualifications notice on July 23, 2026 stating that its Class A common stock no longer meets the $1.00 per share minimum bid price requirement under Nasdaq Listing Rule 5450(a)(1), after trading below that level for 30 consecutive business days.
The notice has no immediate effect on trading; the stock continues on The Nasdaq Global Market under “QSI” and business operations and SEC reporting continue unchanged. Under Nasdaq Listing Rule 5810(c)(3)(A), the company has 180 calendar days, until January 19, 2027, to achieve a closing bid of at least $1.00 for a minimum of 10 consecutive business days, subject to possible extension. If compliance is not regained, Quantum-Si may seek a transfer to The Nasdaq Capital Market and could use a reverse stock split to cure the deficiency; failure to regain compliance could lead to delisting, with only uncertain relief available through a Nasdaq Hearings Panel appeal. The company plans to monitor its share price and evaluate available options.
Quantum-Si Inc general counsel and corporate secretary Christian LaPointe reported two small open-market sales of Class A common stock tied to tax withholding on vested restricted stock units. He sold 7,794 shares on June 22 at a weighted average price of $0.9574 per share and 7,794 shares on June 23 at a weighted average price of $0.8990 per share, for a total of 15,588 shares. The sales were executed under a mandatory sell-to-cover provision for federal, state and local tax withholding and were not discretionary. After these transactions, LaPointe directly holds 1,182,429 Quantum-Si shares.
Quantum-Si Inc Chief Financial Officer Jeffry R. Keyes reported sales of a total of 8,233 shares of Class A Common Stock on June 22 and 23, 2026. According to the disclosure, these transactions were executed under a mandatory sell-to-cover provision to satisfy federal, state and local tax withholding on vested restricted stock units. Following the sales, he directly holds 1,724,349 shares of Class A Common Stock.
Quantum-Si Inc Chief Product Officer John S. Vieceli reported sales of 30,223 shares of Class A Common Stock to cover tax obligations tied to vesting restricted stock units. The transactions occurred on June 22 and June 23 in open-market sales under a mandatory sell-to-cover provision that was set at the grant date and cannot be altered by the individual.
Shares were sold at weighted average prices of $0.9574 and $0.899 per share across price ranges described in the footnotes. After these sales, Vieceli directly holds 1,140,434 shares of Quantum-Si Class A Common Stock, indicating he retains a substantial equity position.
Quantum-Si Inc President & CEO Jeffrey Alan Hawkins reported routine share sales tied to tax withholding on vested equity. On two days, he sold a total of 22,621 shares of Class A Common Stock in open-market transactions under a mandatory sell-to-cover provision for federal, state and local taxes related to previously granted restricted stock units. The sales occurred at weighted average prices around $0.96 and $0.90 per share, and he held 3,669,802 shares directly after the transactions.
Quantum-Si Incorporated reported a proposed sale of Class A Common Stock via a Form 144 filing. The filing lists Restricted Stock Unit vesting on 06/20/2026 totaling 60,425 shares and notes broker Morgan Stanley Smith Barney LLC. Timing and cash‑flow treatment are those shown in the filing.