Wyo. Stat. § 11-23-302: Transportation to another state prohibited without inspection; proof of ownership required.

Without the consent of the owner, or agent, it is unlawful to transport or cause to be transported carcasses of horses, mules, cattle or sheep from Wyoming to any other state without prior inspection for brands and marks and the issuance of a certificate attesting the inspection by an inspector, who shall require proof of ownership by brand record, bill of sale, or both.