MENLO PARK, Calif. — A federal appeals court rolled back rules intended to deter irritating telemarketing robocalls, saying they were too broad.

The U.S. Court of Appeals for the District of Columbia Circuit said that 2015 regulations from the Federal Communications Commission could wrongly classify every smartphone as an autodialing device subject to anti-robocall fines. Those 2015 rules attempted to graft modern definitions onto a 1991 law that predated the iPhone by more than 15 years.

The court also struck down rules that could levy fines on telemarketers who repeatedly call phone numbers reassigned to people who have opted out of such calls.

FCC Commissioner Jessica Rosenworcel said in a tweet the ruling was “not good.” In a statement, she said, “robocalls will continue to increase unless the FCC does something about it.”