Complex sentence: The Tubbs and Easy characters were owned by the "Newspaper Enterprise Association" syndicate and creator Roy Crane abandoned the strips in 1943 to begin "Buz Sawyer", a strip he would own outright.
Split into simpler sentences: The Tubbs and Easy characters were owned by the Newspaper Enterprise Association syndicate. Crane left that syndicate and abandoned the strips in 1943 to begin "Buz Sawyer", a strip he would own outright.