The United States Patent and Trademark Office (USPTO) functions as a for-profit agency under the US Department of Commerce working on revenue collected through user fees. It is required under Article 1, Section 8 of the US Constitution to promote scientific inquiry and securing exclusive rights of ownership to authors and inventors (patents) as well as manage commercial aspects of property rights (trademarks).
The agency, after examination and upon approval, adds a trademark or service mark to either the Principal or Supplemental Register depending on the distinctiveness of the mark. It works to support interstate and international trade working in cooperation with US state-level trademark authorities.