adverse possession vs ownership

adverse possession

noun
  • A means of acquiring title to another's real property without compensation by occupying the property in a manner that has under common law the requirements of being actual, open and notorious, exclusive, hostile, under cover of claim or right, and continuous for a certain number of years. 

ownership

noun
  • The state of having complete legal control of something; possession; proprietorship. 

  • Responsibility for something. 

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