The Supreme Court held that Congress lacked constitutional power over trademarks in 1879

Evidence

The 1870 law that codified patent and copyright law applied to trademarks, too. But the Supreme Court, in 1879, held that the power of Congress, given by the Constitution, to pass laws about patents and copyrights, did not give power to Congress to regulate trademarks. State statutes partly filled the gap. And the courts continued to rework and define the trademark laws of the states. — Lawrence M. Friedman, A History of American Law, 2524

Categorization

• XREF: A classic instance of enumerated-powers limits on federal legislation — connects to the course’s constitutional federalism thread.