In 1978, 20th Century Fox sued Universal claiming that 'Battlestar Galactica' infringed on 'Star Wars'. Universal countersued, alleging that 'Star Wars' stole from their 1972 film, 'Silent Running'
The case ended up dragging on for five years and made it to the Ninth Circuit Court of Appeals. However, for such a major case, the ending is not very satisfying. The two sides opted to settle ahead of a potential trial, leaving the allegations unresolved.