When the Marx Brothers announced in 1946 that their upcoming film was called A Night in Casablanca, Warner Bros threatened to sue for breach of copyright. Warner had produced the great hit “Casablanca” four years earlier, and insisted the funny men were trying to cash in on it. But Groucho was no slouch. He had his lawyer threaten Warner Brothers with breach of copyright for using the word brothers. The Marx boys won, as they were brothers before the Warners had formed the company. A Night in Casablanca turned out also to be a great hit.