Copolymer, process for the production thereof, and molded article thereof

1. Field of the Invention A copolymer of (a)ethylene and/or an -olefin, (b) a cyclic olefin and (c) an alkenyl aromatic hydrocarbon, having acyclic olefin content of 0.01 to 66 mol % and a styrene content of 3 to 99 mol %, wherein the styrene content is more than a half of the cyclic olefin content, a process for producing the copolymer with a specific catalyst and a molded article made from the copolymer. The copolymer and molded article thereof are transparent, and excellent in flexibility and heat resistance.