SEC Form 4 · accession 0001193125-26-345826

Latigo Biotherapeutics, Inc. · LTGO

Statement of changes in beneficial ownership, as filed. Original on EDGAR ↗

Reporting owner

Sanofi

10% Owner

Period of report

Aug 10, 2026

Accepted (ET)

Aug 12, 2026 · 8:18 am EDT

Rule 10b5-1 plan

box not checked

Issuer CIK

0002056611

Table I — non-derivative securities

Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock^F1,F3	Aug 10, 2026	C	494,800	—	A	494,800	I	See footnote
Common Stock^F2,F3	Aug 10, 2026	C	177,978	—	A	672,788	I	See footnote

Table II — derivative securities

Security	Conv. / exercise price	Date	Code	Shares	A/D	Exercisable	Expires	Underlying	Underlying shares	Owned after	D/I
Series B Preferred Stock^F1,F3	—	Aug 10, 2026	C	494,800	D	—	—	Common Stock	494,800	0	I
Convertible Promissory Note^F2,F3	—	Aug 10, 2026	C	177,978	D	—	—	Common Stock	177,978	0	I

Explanation of responses

F1The 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.
F2The 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.
F3Sanofi beneficially owns the securities reported herein through various wholly-owned subsidiaries.

Remarks

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.