X0609 4 2026-09-01 0 0001880613 Direct Digital Holdings, Inc. DRCT 0001896664 Walker Mark D false C/O DIRECT DIGITAL HOLDINGS, INC. 1177 WEST LOOP SOUT, SUITE 1300 HOUSTON TX 77027 1 1 0 0 Chairman and CEO 0 Class A Common Stock, par value $0.001 per share 2026-09-01 2026-09-01 4 S 0 1636 2.0572 D 8364 I By AJN Energy & Transport Ventures, LLC Class A Common Stock, par value $0.001 per share 2026-09-02 2026-09-02 4 S 0 500 1.90 D 7864 I By AJN Energy & Transport Ventures, LLC Class A Common Stock, par value $0.001 per share 221 D This transaction was executed in multiple trades at prices ranging from $1.95 to $2.165 per share. The price reported above reflects the weighted average purchase price on the date indicated. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares sold at each separate price within the range set forth in this footnote. /s/ Mark Walker 2026-09-03