Neil Lerner

Neil Lerner, Chief Accounting Officer of Compass Therapeutics, Inc., acquired 2,500 shares of Common Stock on September 24, 2026, at a price of $1.14 per share. This transaction was made under the code "P" for purchase and "A" for acquired. Following this transaction, Lerner owns 400,000 shares of Common Stock. A portion of these shares, specifically 62,500, are unvested restricted stock units (RSUs) granted on January 2, 2026, which are subject to vesting conditions and will vest in four equal annual installments, with the first installment vesting on January 2, 2027. The filing is Form 4, indicating a statement of changes in beneficial ownership of securities.