Va. Code § 59.1-501.8: Proof and effect of authentication

(a) Authentication may be proven in any manner, including a showing that a party made use of information or access that could have been available only if it engaged in conduct or operations that authenticated the record or term.(b) Compliance with a commercially reasonable attribution procedure agreed to or adopted by the parties or established by law for authenticating a record authenticates the record as a matter of law.2000, cc. 101, 996.