The Hollywood Reporter writer Borys Kit has heard from several sources that the Han Solo movie will explain how Lando Calrissian lost the Millennium Falcon to Han Solo.
Since then, the only thing Lucasfilm he revealed about the transition of ownership is that Lando lost the ship in a game of sabacc, a popular card game in a galaxy far, far away.
Fans learned in The Empire Strikes Back that Han wasn’t the Millennium Falcon’s original owner when Lando asked what he’d done to “his” ship, leading Han to remind his buddy that he won it “fair and square.”
It may be a while until this is confirmed or denied, but it’s certainly plausible.