Voice over Internet Protocol patents asserted against Apple Inc., AT&T Corp., Verizon Wireless Services LLC, and Twitter Inc. didn’t cover patent-eligible subject matter, the Northern District of California ruled March 25.

The U.S. District Court for the Northern District of California dismissed the patent infringement case and invalidated Voip-Pal.com Inc.'s patents because they were directed to the abstract idea of routing phone calls.

The ruling shows which technologies may fail the patent eligibility test the U.S. Supreme Court laid out in 2014 in Alice v. CLS Bank. A patented invention must not be directed at an abstract...