The part that Ellison claimed was ripping off his work was the Terminator traveling back in time to kill someone in the present day, which was similar to his Outer Limits episode "Soldier". There are a lot of things that may or may not have inspired Terminator, from "Soldier" to "Second Variety" to "Colossus: The Forbin Project" (a 1970 movie which featured a military computer taking over the world similar to Skynet).