U.S. Constitution Article I
Section 8: Powers of Congress
To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries
The Patent Act of 1790 grants the applicant: “the sole and exclusive right and liberty of making, constructing, using and vending to others to be used, the said invention or discovery.”
Patent ownership operated mostly that way for inventors until passage of the America Invents Act of 2011 when the Patent Trial and Appeal Board (PTAB – aka the “patent death squad”) was born.