inoperative vs prepatent

inoperative

adj
  • No longer legally binding. 

  • Not working or functioning; either idle or broken. 

prepatent

adj
  • Prior to the existence of a legal patent. 

  • Before symptoms (especially of infection) become manifest. 

How often have the words inoperative and prepatent occurred in a corpus of books? (source: Google Ngram Viewer )