John S. Vieceli - 12 Mar 2026 Form 4 Insider Report for Quantum-Si Inc (QSI)

Reporting relationship: Chief Product Officer
Issuer ticker: QSI
Reported as of: 12 Mar 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 16 Mar 2026, 16:14:14 UTC
Prior SEC filing: 22 Dec 2025
Next SEC filing: 24 Mar 2026
Source filing: View source filing
Reporting owner signature: /s/ Christian LaPointe, Ph.D., Attorney-in-Fact.

Key filing fact

John S. Vieceli filed Form 4 for Quantum-Si Inc (QSI) on 16 Mar 2026.

Key facts

This page summarizes John S. Vieceli's Form 4 filing for Quantum-Si Inc (QSI).
2 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 16 Mar 2026, 16:14.

Change

Previous filing in this sequence was filed on 22 Dec 2025.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0002032947 Primary reporting owner

Vieceli John S.

Relationship: Chief Product Officer
Address: C/O QUANTUM-SI INCORPORATED, 29 BUSINESS PARK DRIVE, BRANFORD
Signature: /s/ Christian LaPointe, Ph.D., Attorney-in-Fact.
Signature date: 16 Mar 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

QSI transaction

Class A Common Stock

Award

Transaction value
Shares: +391,681
Change %: +49%
Price: $0.000000^*
Shares after: 1,192,654
Date: 12 Mar 2026
Ownership: Direct
Footnotes: F1

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

QSI transaction Derivative

Stock Option (Right to Buy)

Award

Transaction value
Shares: +468,508
Change %
Price: $0.000000^*
Shares after: 468,508
Date: 12 Mar 2026
Ownership: Direct
Underlying class: Class A Common Stock
Underlying amount: 468,508
Exercise price: $0.9760
Footnotes: F2

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 2 footnotes

Footnote F1

The grant consists of restricted stock units ("RSUs"). Each RSU represents the right to receive one share of common stock upon vesting. The RSUs shall vest in 16 equal quarterly installments beginning on June 20, 2026 until fully vested, subject to continued service through the applicable vesting date.

Footnote F2

The shares underlying this option shall vest in equal quarterly installments beginning on June 20, 2026 until fully vested, subject to continued service through the applicable vesting dates.