unclaimed vs unsigned

unclaimed

adj
  • Not claimed. 

unsigned

adj
  • Lacking a signature, unendorsed. 

  • Not accepting negative numbers; having only a positive absolute value. 

  • Not signed to an organization such as a sports club or record label. 

noun
  • A numeric value or variable that has no sign and can only be positive. 

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