The United States Patent and Trademark Office (USPTO) promotes the progress of science and the useful arts by securing for limited times to inventors the exclusive right to their respective discoveries per Article 1, Section 8, Clause 8 of the United States Constitution:
The Congress shall have Power . . . 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. -- United States Constitution, Article 1, Section 8, Clause 8.