York Charles N II 4

What Happened
Charles N. York II, Day One Biopharmaceuticals' COO and CFO, had multiple RSU awards convert to common stock on Feb 15, 2026 and subsequently sold shares to cover tax obligations. The filing shows RSU exercises/settlements on Feb 15 totaling 23,375 shares (several derivative conversions), and a separate open-market sale on Feb 17 of 6,065 shares at a weighted average price of $11.60 for total proceeds of $70,359. Several of the settled shares were treated as disposed at $0 to satisfy tax withholding tied to the RSU settlement.

Key Details

• Transaction types: RSU settlement/exercise (derivative code M) on 2026-02-15; open-market sale (S) on 2026-02-17.
• Shares involved: RSU settlements listed totaling 23,375 shares; 23,375 shares shown as disposed at $0 (tax withholding); 6,065 shares sold in open market for $11.60 (weighted average) = $70,359.
• Sale price range: Block trades that included these shares were at prices ranging $11.195–$11.8508 (weighted avg reported).
• Purpose: Footnote states the sale was solely to cover the reporting person's tax liability related to RSU settlement.
• Shares owned after transaction: Not specified in the provided filing.
• Timeliness: Filing does not indicate lateness.

Context
The "M" derivative entries reflect RSU settlements (each RSU converts into one share upon settlement with no purchase price). The $0 disposals correspond to shares withheld to satisfy tax obligations (typical for RSU vesting). The additional open-market sale appears to be part of block trades to fully cover taxes; this is a routine, non-speculative insider sale rather than a purchase signal.