No, no WGA signatory company can “screw the writer” since credit are determined by the WGA. The companies must abide by the credit rules and when there’s more than one writer vying it does to arbitration (unless they agree). It’s quite complicated but allow me to explain!
I’ve been an arbiter dozens of times and even the arbiters get confused. I’m going to first break down how it works and then explain why it matters.
First of all there are a lot of confusing terms but basically as others have correctly stated a full writing credit is called “written by” and it consists of 2 parts, “story” and “screenplay” (in tv screenplay is called “teleplay”). 1 writer could get story & another screenplay.
Or on big tentpole movies 10 writers can share story and screenplay is lots of exciting ways! But “story” is the lesser credit and “screenplay” the bigger one (more on this later) but together they equal “written by.” So if it’s all 1 writer it’s written by.
Aha, but wait! I’ve seen teleplay by only with no story credit! That’s true. Because movies can be “original” or “adaptions.” (These are defined terms. Original is what it sounds like but adaptation is EVERYTHING else: sequels, remakes, books, games, any prior IP).
Original projects have story and screenplay components so the credit is split between participating writers who earn credit or get combined into written by if story and screenplay are by the same writer(s). But adaptations sometimes don’t have story credit.
If the underlying IP already has the same story there might not be a new story credit. This is also where you see the rarer oddball credits like screen story by or sometimes adaptation by (which is a rare but real WGA credit).
So long story short, you were right that an absence of a story credit means it was adapted.
This is all separate from the “created by” credit which is a separate deal altogether. (The lesser credit there is “developed by”.)
But now we get to why it matters. Of course credit is what helps careers but there’s also the minor issue of money! Money is based on credit in 3 ways in film and 3 different ways in tv.
In film, you will be paid for writing based on number of steps (treatment, draft, revision) and this is guaranteed money. A production bonus is paid IF the movie gets made AND you earn screenplay credit. There is no bonus for story credit! It’s all or nothing but the good news is
“Screenplay by” and “written by” are equal for production bonus. If A gets story and B gets screenplay, A gets no bonus and B gets the bonus negotiated for. Shared credit means 1/2 the bonus.
But the third factor is residuals. Story is 25% of the writer residuals and screenplay is 75%. So more credit means more money here! So to clarify, credit has no impact on the original guaranteed fee but is huge for bonus and residuals.
In tv, it’s rarer to create a show and be rewritten but it happens. That pilot can be artbited and credit on the pilot determines the created by credit. Created by credit is what triggers the negotiated per episode royalty and the back end participation.
But the pilot is treated like any other episode for residuals. So shared credit means shared residuals but residuals are the same more or less for every episode including the pilot.
So long story short in tv the pilot script credit goes to created by which triggers royalties and back end but not residuals except for that episode. /fin
