Gossamer Bio Director Daniel O Receives 10,000-Share Option

What Happened
Daniel Thomas O, a director of Gossamer Bio, received a derivative award (an option) for 10,000 shares on 2026-09-23. The reported acquisition price is $0.00 (the filing shows $0 value at grant). This was a grant/award (not an open-market purchase or sale) — a form of compensation/retention.

Key Details

• Transaction date: 2026-09-23; Form 4 filed: 2026-09-25 (filed within the typical two-business-day window).
• Instrument: Derivative (option/award) for 10,000 shares, reported at $0.00 per share on grant.
• Vesting: The entire award becomes fully vested and exercisable on the first anniversary of the grant date, subject to continued service on the board (footnote).
• Shares owned after transaction: Not specified in the provided filing excerpt.
• No sale or cash purchase occurred; this is a compensation grant rather than a market trade.

Context
This transaction is a standard director compensation grant — it gives the director the right to the underlying shares subject to vesting rather than an immediate share purchase or sale. Such awards are common for retaining board members and do not by themselves indicate the director bought or sold stock on the open market.