X0609 4 2026-06-24 0 0002109876 Mountain Crest Acquisition 6 Corp. MCAH 0001811534 Liu Suying false C/O MOUNTAIN CREST ACQUISITION 6 CORP., 524 BROADWAY, 11TH FLOOR, NEW YORK NY 10012 1 1 1 0 CEO and CFO 0 Ordinary shares 2026-06-24 4 J 0 385714 D 2596429 I See Footnote Represents the forfeiture for no consideration of 385,714 ordinary shares, par value $0.0001 per share, of Mountain Crest Acquisition 6 Corp. (the "Issuer") held by Mountain Crest Holdings 6 LLC because the underwriters of the Issuer's initial public offering did not exercise their over-allotment option. The forfeited shares were the full 385,714 founder shares that were subject to forfeiture depending on the extent to which the underwriters' over-allotment option was exercised. Dr. Suying Liu controls Mountain Crest Holdings 6 LLC. As such, he may be deemed to have or share beneficial ownership of the securities held directly by Mountain Crest Holdings 6 LLC. Suying Liu disclaims any beneficial ownership of the reported shares other than to the extent of any pecuniary interest he may have therein, directly or indirectly. /s/ Suying Liu Sole Member 2026-06-25