Indy,

The lawsuit which resulted in the U.S. paying Mauser royalties mostly involved the Mauser top insertion clip, not the action itself. Though there were certainly some similarities between the actions, there were enough differences to avoid that issue.

The 1917 Enfield was considerably different from the Lee-Enfield action, with more resemblance to a cock-on-closing pre-98 Mauser action.

“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.”
John Steinbeck