I thought it was time to expand my Captain Beyond collection beyond the first album, and somehow that led me to the Wikipedia page for Rod Evans, singer for Captain Beyond and prior to that original singer for Deep Purple. And that's where i saw this:
Tour of imitation band
In 1980 he was approached by a management company which specialized in questionably-reformed bands with well-known names, and he began to tour under the Deep Purple name accompanied by unknown session musicians...
After several shows ended in near riots, Evans was sued by the management of the real Deep Purple and they were awarded damages of $672,000. As a result of the lawsuit, Evans no longer receives royalties from the band's first three albums