Patent Troll
  
They really are trolls. They hide in the legal bushes, just waiting for some little tiny wrinkle in the fine print to then jump out and lay claim to a given patent or process, sue everyone around them, and collect legal ransom from the claim owners.
These angry lawyers typically live inside of shadowy, unknown, or ambiguous areas of the law where the threat of a big lawsuit is often enough to win ransom money from fat-pocketed corporations, just wanting to continue the next 17 months until their current CEO can fold into retirement golf.