The United States Supreme Court held that a transferor forum's state law applies after a change in venue is granted in accordance with 28 USC section 1404(a).
Ferens v Deere & Company, 494 US ___ , 110 S Ct 1274, 58 USLW 4333 (1990).
George S. Hickmann,
Choice of Law - Change in Venue - Federal Courts,
Duq. L. Rev.
Available at: https://dsc.duq.edu/dlr/vol29/iss1/12