Forget it. I really can't be bothered. Harve Bennett wrote Star Trek II. Congrats.
Also, Philip Kaufman wrote Raiders of the Lost Ark. I guess Lawrence Kasden will have to give back that Saturn Award.
When the "story" and "screenplay" credits are shared by a single writer (or writing team) the credit is "written by."
Or, to crib from Wikipedia:
There is a common misconception that a "story by" credit may be given to a person who simply has the story idea for a film or television program. This is never the case, as all writing credits are for actual writing; a written story document or treatment, or in some cases, a complete script. In such cases, a screenwriter produces an original screenplay that subsequently undergoes a "page one rewrite" by a different writer or writers that produces a new and significantly different draft, as determined by the WGA. In many such cases, the original author receives the "story by" rather than "screenplay by" credit. This is known as the Irreducible Story Minimum.
Also, the Saturn Awards are nice, but the AMPAS awards screenwriting Oscars to anyone receiving "story" or "screenplay" credit.