Denny O'Neil was a comic book writer and editor until his retirement, known mostly for his involvement with Batman. When Hasbro approached Marvel Comics to develop a story for their Transformers toyline, he and Jim Shooter came up with the initial story treatment.
Denny O'Neil named Optimus Prime.
However, Hasbro rejected many of their proposed character names and some of the concepts, so their duties were passed down to Bob Budiansky.