U.S. Constitution, Article I, Section 8, Clause 8:
[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.
Congress’s power over trademarks, another form of intellectual property, does not derive from the Intellectual Property (IP) Clause. In The Trade-Mark Cases, decided in 1879, the Supreme Court held that Congress lacked power under the IP Clause to provide for trademark protection because trademarks need not be original, creative, novel, nor inventive. As a result, the Court was
unable to see any such power [to protect trademarks] in the constitutional provision concerning authors and inventors, and their writings and discoveries. In the twentieth century, however, courts have sustained federal trademark legislation as an exercise of Congress’s power under the Commerce Clause.
As with other forms of intellectual property, Congress’s power over trademarks cannot be used in ways that infringe the constitutional rights of individuals. For example, because trademarks are considered private speech under the First Amendment, the government generally cannot engage in viewpoint discrimination in trademark registration decisions.