From the movie Logan (2017)
A mutant hunter tortures a mutant called Calliban who can track another mutant Laura.
The hunter says
She's not a natural like you. She's a business mistake, a R&D gone bad. There's liability. They can't have things with patents running around, hurting people, can they? We need to get her off the board before she hurts anybody else
What exactly does "get off the board" mean? Does he mean a metaphorical board like a checkerboard or it's just idiomatic like "we need to capture and hide her"?