STOCK TITAN

Quantum-Si (QSI) director awarded 251,185 options at $0.8539 strike

Filing Impact
(Neutral)
Filing Sentiment
(Neutral)
Form Type
4

Rhea-AI Filing Summary

ROTHBERG JONATHAN M reported acquisition or exercise transactions in this Form 4 filing.

Quantum-Si Inc director and 10% owner Jonathan M. Rothberg reported a grant of 251,185 stock options, each exercisable for one share of Class A Common Stock at $0.8539 per share. The options vest on the date of the issuer’s next regular annual stockholders meeting, subject to his continued service.

After this grant, he holds 2,568,443 Class A Common Stock shares directly and has additional indirect holdings, including 1,993,750 Class B shares through 4C Holdings V, LLC and 17,943,750 Class B shares through 4C Holdings I, LLC. Some shares are held by entities managed by Dr. Rothberg and by family members, and he disclaims beneficial ownership of shares held by his spouse and by 23rd Century Capital LLC.

Positive

  • None.

Negative

  • None.
Insider ROTHBERG JONATHAN M
Role null
Type Security Shares Price Value
Grant/Award Stock Option (right to buy) 251,185 $0.00 --
holding Class A Common Stock -- -- --
holding Class A Common Stock -- -- --
holding Class A Common Stock -- -- --
holding Class A Common Stock -- -- --
holding Class A Common Stock -- -- --
holding Class A Common Stock -- -- --
holding Class A Common Stock -- -- --
holding Class A Common Stock -- -- --
holding Class B Common Stock -- -- --
holding Class B Common Stock -- -- --
Holdings After Transaction: Stock Option (right to buy) — 251,185 shares (Direct, null); Class A Common Stock — 1,904,866 shares (Indirect, By NVR TR, LLC); Class A Common Stock — 2,568,443 shares (Direct, null); Class B Common Stock — 17,943,750 shares (Indirect, By 4C Holdings I, LLC)
Footnotes (1)
  1. Dr. Rothberg is the sole manager of 4C Holdings I, LLC, 4C Holdings V, LLC, NVR TR, LLC, JNR TR, LLC, GBR TR, LLC, EJR TR, LLC and JAR TR, LLC and Dr. Rothberg is the spouse of Bonnie E. Gould Rothberg MD and Dr. Rothberg's son is the manager of 23rd Century Capital LLC. Dr. Rothberg disclaims beneficial ownership of the shares held by his spouse and 23rd Century Capital LLC. The shares underlying this option vest on the date of the Issuer's next regular annual stockholders meeting, subject to continued service through the applicable vesting date.
Option grant size 251,185 options Stock Option (right to buy) granted to Jonathan M. Rothberg
Option exercise price $0.8539 per share Exercise price for Class A Common Stock underlying options
Options expiration May 18, 2036 Expiration date of the stock option grant
Underlying shares 251,185 Class A shares Shares of Class A Common Stock underlying the options
Direct Class A holdings 2,568,443 shares Class A Common Stock held directly after reported transactions
4C Holdings V Class B 1,993,750 shares Class B Common Stock held indirectly via 4C Holdings V, LLC
4C Holdings I Class B 17,943,750 shares Class B Common Stock held indirectly via 4C Holdings I, LLC
Stock Option (right to buy) financial
"security_title: "Stock Option (right to buy)""
Class A Common Stock financial
"underlying_security_title: "Class A Common Stock""
Class A common stock is a category of a company’s shares that carries a specific set of ownership rights—most commonly defined voting power and claims on dividends—set out in the company’s charter. For investors it matters because the class determines how much influence you have over corporate decisions, the share’s likely dividend and trading behavior, and how it compares in value to other share classes, like choosing a particular seat with different privileges at the company’s decision-making table.
Class B Common Stock financial
"security_title: "Class B Common Stock""
A class B common stock is one of multiple types of a company’s ordinary shares that carries specific rights—often different voting power or dividend priority—compared with other classes. For investors it matters because those differences affect how much influence you have over company decisions, the income you might receive, and how freely the shares trade; think of it like owning a car with different keys: some keys let you start the engine and open the trunk, others only unlock the door.
beneficial ownership financial
"Dr. Rothberg disclaims beneficial ownership of the shares held by his spouse"
Beneficial ownership means the person or entity that actually enjoys the benefits of owning shares or other assets — such as receiving dividends, voting rights, or price gains — even if the legal title is held in another name. For investors it matters because knowing who truly controls and profits from a company reveals who can influence decisions, exposes potential conflicts of interest or hidden concentration of power, and affects transparency and risk in the stock.
regular annual stockholders meeting financial
"vest on the date of the Issuer's next regular annual stockholders meeting"
SEC Form 4
FORM 4UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940
OMB APPROVAL
OMB Number:3235-0287
Estimated average burden
hours per response:0.5
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.
1. Name and Address of Reporting Person*
ROTHBERG JONATHAN M

(Last)(First)(Middle)
C/O QUANTUM-SI INCORPORATED
29 BUSINESS PARK DRIVE

(Street)
BRANFORD CONNECTICUT 06405

(City)(State)(Zip)

UNITED STATES

(Country)
2. Issuer Name and Ticker or Trading Symbol
Quantum-Si Inc [ QSI ]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
XDirectorX10% Owner
Officer (give title below)Other (specify below)
2a. Foreign Trading Symbol
3. Date of Earliest Transaction (Month/Day/Year)
05/18/2026
6. Individual or Joint/Group Filing (Check Applicable Line)
XForm filed by One Reporting Person
Form filed by More than One Reporting Person
4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year)2A. Deemed Execution Date, if any (Month/Day/Year)3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeVAmount(A) or (D)Price
Class A Common Stock1,904,866IBy NVR TR, LLC(1)
Class A Common Stock1,930,960IBy JNR TR, LLC(1)
Class A Common Stock1,930,960IBy GBR TR, LLC(1)
Class A Common Stock1,930,960IBy EJR TR, LLC(1)
Class A Common Stock2,568,443D
Class A Common Stock1,250,000IBy JAR TR, LLC(1)
Class A Common Stock1,917,067IBy 23rd Century Capital LLC(1)
Class A Common Stock273,422IBy Bonnie E Gould Rothberg MD(1)
Class B Common Stock17,943,750IBy 4C Holdings I, LLC(1)
Class B Common Stock1,993,750IBy 4C Holdings V, LLC(1)
Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year)3A. Deemed Execution Date, if any (Month/Day/Year)4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 6. Date Exercisable and Expiration Date (Month/Day/Year)7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeV(A)(D)Date ExercisableExpiration DateTitleAmount or Number of Shares
Stock Option (right to buy)$0.853905/18/2026A251,185 (2)05/18/2036Class A Common Stock251,185$0251,185D
Explanation of Responses:
1. Dr. Rothberg is the sole manager of 4C Holdings I, LLC, 4C Holdings V, LLC, NVR TR, LLC, JNR TR, LLC, GBR TR, LLC, EJR TR, LLC and JAR TR, LLC and Dr. Rothberg is the spouse of Bonnie E. Gould Rothberg MD and Dr. Rothberg's son is the manager of 23rd Century Capital LLC. Dr. Rothberg disclaims beneficial ownership of the shares held by his spouse and 23rd Century Capital LLC.
2. The shares underlying this option vest on the date of the Issuer's next regular annual stockholders meeting, subject to continued service through the applicable vesting date.
/s/ Christian LaPointe, Ph.D., Attorney-in-Fact.05/20/2026
** Signature of Reporting PersonDate
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

FAQ

What did Quantum-Si (QSI) insider Jonathan Rothberg report on this Form 4?

Jonathan M. Rothberg reported receiving a grant of 251,185 stock options for Quantum-Si Class A Common Stock at an exercise price of $0.8539 per share. These options represent compensation rather than an open-market purchase or sale of existing shares.

How many Quantum-Si stock options were granted to Jonathan Rothberg and at what price?

He was granted 251,185 stock options, each with an exercise price of $0.8539 per share for Quantum-Si Class A Common Stock. The options give him the right to buy shares at that price if they vest and are exercised before expiration.

When do Jonathan Rothberg’s newly granted Quantum-Si options vest and expire?

The shares underlying this option vest on the date of Quantum-Si’s next regular annual stockholders meeting, contingent on continued service. The options expire on May 18, 2036, giving a long window during which they can potentially be exercised once vested.

What are Jonathan Rothberg’s direct Quantum-Si Class A share holdings after this filing?

Following the reported transactions, Jonathan Rothberg directly holds 2,568,443 shares of Quantum-Si Class A Common Stock. This direct position is separate from additional indirect holdings he reports through various LLCs and family-related entities listed in the Form 4.

What indirect Quantum-Si holdings are associated with Jonathan Rothberg via LLCs?

Indirectly, he reports 1,993,750 Quantum-Si Class B shares through 4C Holdings V, LLC and 17,943,750 Class B shares through 4C Holdings I, LLC, among other entities. He is sole manager of several LLCs but disclaims beneficial ownership of shares held by his spouse and 23rd Century Capital LLC.

Does Jonathan Rothberg disclaim beneficial ownership of any Quantum-Si shares in this filing?

Yes. He notes that he is the spouse of Bonnie E. Gould Rothberg MD and that his son manages 23rd Century Capital LLC, and he expressly disclaims beneficial ownership of Quantum-Si shares held by his spouse and by 23rd Century Capital LLC, despite reporting them as indirect holdings.