Bethesda has been denied a restraining order against a Fallout MMO developed between Masthead and Interplay.

In a ruling by US district judge John F. Walter, Bethesda failed to show it would be "irreparably prejudiced" if the order was not granted.

"Indeed, [Bethesda] was aware as early as February 2011 that Masthead was potentially infringing its copyrights... Yet, Plaintiff waited seven months to apply for ex parte relief, Gamasutra reports.

"The Court finds that Plaintiff unreasonably delayed in seeking relief, and that the emergency that allegedly justifies a [temporary restraining order] is self-created."

Bethesda bought the Fallout license from Interplay in 2009, then later sued Interplay in 2009 for taking too long to develop a Fallout MMO.