X0609 4 2026-08-10 true 0002056611 Latigo Biotherapeutics, Inc. LTGO 0001121404 Sanofi true 46 AVENUE DE LA GRANDE ARMEE PARIS I0 75017 FRANCE false false true false false Common Stock 2026-08-10 4 C false 494800 A 494800 I See footnote Common Stock 2026-08-10 4 C false 177978 A 672788 I See footnote Series B Preferred Stock 2026-08-10 4 C false 494800 D Common Stock 494800 0 I See footnote Convertible Promissory Note 2026-08-10 4 C false 177978 D Common Stock 177978 0 I See footnote The Series B Convertible Preferred Stock (the "Preferred Stock") converted automatically into shares of common stock on a one-for-one basis upon the closing of the Issuer's initial public offering on August 10, 2026 (the "IPO") without payment of consideration. The principal amount of the convertible promissory note (the "Note"), together with any accrued but unpaid interest, automatically converted into shares of common stock upon the closing of the IPO at a conversion price equal to the IPO price of the common stock. Sanofi beneficially owns the securities reported herein through various wholly-owned subsidiaries. Immediately upon consummation of the IPO, Sanofi's beneficial ownership of the common stock fell below 10%, as a result of the issuance of additional shares of common stock. The convertibility and expiration of the Preferred Stock and Note prior to the IPO are described in Sanofi's Form 3, filed with the Securities and Exchange Commission on August 12, 2026. /s/ Alexandra Roger, as attorney-in-fact for Sanofi 2026-08-12