registered trademark vs trade name

registered trademark

noun
  • A trademark that has been officially registered with the government by its owner. Indicated by the symbol ®. 

trade name

noun
  • A name used to identify a commercial product or service; may or may not be registered as a trademark. 

  • The name under which a business or firm operates. 

How often have the words registered trademark and trade name occurred in a corpus of books? (source: Google Ngram Viewer )