Leeds have sold a minority stake in the club to the San Francisco 49ers' investment group.
Reports say the NFL franchise have invested £10million in the Sky Bet Championship side.
"This strategic partnership enables Leeds United to align with and gain invaluable expertise from the owners of one of the biggest global sports entities," said Leeds owner Andrea Radrizzani.
"The 49ers are an innovative, successful organisation and we are delighted to have access to such a rich source of business and sporting expertise.
"This exciting partnership builds on the foundations we have laid down at the club in the last 12 months and we can assure supporters that the funds invested will go towards improving results on the pitch."