X0202 SCHEDULE 13G/A 0001896206 XXXXXXXX LIVE 1 Common Stock, par value $0.0001 per share 05/05/2026 0001844505 QT IMAGING HOLDINGS, INC. 746962109 3 HAMILTON LANDING SUITE 160 NOVATO CA 94949 Rule 13d-1(c) Alta Partners LLC NY 540842.00 0.00 540842.00 540842.00 540842.00 4.3 OO QT IMAGING HOLDINGS, INC. 3 HAMILTON LANDING, SUITE 160, NOVATO, CALIFORNIA, 94949. Alta Partners LLC 1205 Franklin Avenue Garden City, New York 11530 New York Limited Liability Company Y 540,842 shares of Common Stock, representing shares issuable upon exercise of warrants. 4.3% 540,842 shares of Common Stock 0 Shares of Common Stock 540,842 shares of Common Stock 0 Shares of Common Stock Y Y Y Y Y N By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11. By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11. Alta Partners LLC /s/ Steven Cohen 05/08/2026