Complex sentence: He left Lantz in 1965 to work briefly for Hanna-Barbera Productions, before moving over to DePatie-Freleng Enterprises to direct "Pink Panther" shorts and other cartoon series.
Split into simpler sentences: He left Lantz in 1965 to work briefly for Hanna-Barbera Productions. He later moved over to DePatie-Freleng Enterprises to direct "Pink Panther" shorts and other cartoon series.