Abiopharma

🔍 ARCH Venture Partners XII, LLC (Executive)

Company: Seaport Therapeutics, Inc. (SPTX)

Report Date: 2026-05-04

Detailed Transactions and Holdings:

• Acquired 2,513,686 shares of Common Stock (Direct)
  Date: 2026-05-04 | Code: C | equity_swap_involved: false | shares_owned_after: 2,513,686.00 | transaction_form_type: 4 | Footnotes: F1, F2
• Acquired 2,681,265 shares of Common Stock (Direct)
  Date: 2026-05-04 | Code: C | equity_swap_involved: false | shares_owned_after: 5,194,951.00 | transaction_form_type: 4 | Footnotes: F1, F2
• Acquired 1,100,000 shares of Common Stock at $18.0 per share (Direct)
  Date: 2026-05-04 | Code: P | equity_swap_involved: false | shares_owned_after: 6,294,951.00 | transaction_form_type: 4 | Footnotes: F2
• Sold 2,513,686 shares of Series A-2 Preferred Stock (Derivative)
  Date: 2026-05-04 | Code: C | equity_swap_involved: false | transaction_form_type: 4 | Footnotes: F1, F1, F1, F2
• Sold 2,681,265 shares of Series B Preferred Stock (Derivative)
  Date: 2026-05-04 | Code: C | equity_swap_involved: false | transaction_form_type: 4 | Footnotes: F1, F1, F1, F2

Footnotes:

• F1: Each share of Series A-2 and Series B Preferred Stock (collectively, the "Preferred Stock") was convertible into Common Stock of the Issuer on a one-for-3.1407 basis at the option of the holder, and automatically converted upon the closing of the Issuer's initial public offering without payment of further consideration. The Preferred Stock had no expiration date.
• F2: Shares held directly by ARCH Venture Fund XII, L.P. ("ARCH XII"). ARCH Venture Partners XII, L.P. ("AVP XII LP") is the sole general partner of ARCH XII. ARCH Venture Partners XII, LLC ("AVP XII LLC") is the sole general partner of AVP XII LP. Keith Crandell, Kristina Burow, Steven Gillis and Robert Nelsen are members of the investment committee of AVP XII LLC (the "AVP XII LLC Committee Members"). Each of AVP XII LP and AVP XII LLC may be deemed to beneficially own the shares held by ARCH XII, and each of the AVP XII LLC Committee Members may be deemed to share the power to direct the disposition and vote of the shares held by ARCH XII. Each of AVP XII LP, AVP XII LLC and the AVP XII LLC Committee Members disclaims beneficial ownership except to the extent of their pecuniary interest therein, if any.