Initial Statement of Beneficial Ownership - Cosan S.A.

This filing reports the initial statement of beneficial ownership for Cosan S.A. (CSAN) as of March 18, 2026. The reporting owner, Marcelo Eduardo Martins, who is the Chief Executive Officer and a Director, directly holds 1,960,840 shares of Common Stock (BVMF: CSAN3) and 1,613,666 American Depositary Shares (ADS CSAN1). Additionally, Mr. Martins holds 6,347,353 shares related to the Long-Term Incentive Program. The remarks clarify that each ADS represents four shares of Common Stock and that the shares from the incentive program are subject to vesting periods and potential performance targets, with the reported amount being an estimate that may change prior to actual delivery due to target achievement and tax effects.