Mackay Sean 4
4 · STANDARD BIOTOOLS INC. · Filed May 22, 2026
Research Summary
AI-generated summary of this filing
Standard BioTools (LAB) SVP Sean Mackay Sells 25,729 Shares
What Happened
- Sean Mackay, SVP & Chief Business Officer of Standard BioTools (ticker: LAB), had 25,729 shares withheld/disposed to satisfy tax withholding obligations tied to the vesting of restricted stock units (RSUs). The withholding was recorded at $1.00 per share for a total of $25,729.
Key Details
- Transaction date: 2026-05-20; Form 4 filed: 2026-05-22 (appears timely).
- Price reported: $1.00 per share; total value: $25,729.
- Transaction code: F — shares withheld to cover tax liability (not an open-market sale).
- Shares owned after the transaction: not specified in the provided filing.
- Footnote: The withheld shares relate to RSUs granted on May 20, 2024; March 21, 2025; and March 20, 2026 (original grants reported on prior Forms 3/4).
Context
- This was a tax-withholding disposition (routine). Such withholdings are common when RSUs vest and do not necessarily signal insider sentiment about the company’s stock.
- For retail investors: purchases are typically more informative than routine withholdings; this entry reflects compensation tax mechanics rather than a deliberate investment decision.
Insider Transaction Report
Form 4
Mackay Sean
SVP & Chief Business Officer
Transactions
- Tax Payment
Common Stock
[F1]2026-05-20$1.00/sh−25,729$25,729→ 1,006,552 total
Footnotes (1)
- [F1]The shares were withheld from the reporting person to satisfy the tax withholding obligations that arose upon the vesting of restricted stock units granted to the reporting person on May 20, 2024, March 21, 2025 and March 20, 2026, which grants were originally reported on Form 3 and Form 4s filed with the U.S. Securities and Exchange Commission on September 3, 2024, March 24, 2025 and April 8, 2026, respectively.
Signature
/s/ Sean Mackay by Tomone Tanaka, Attorney-in-Fact|2026-05-22