SAN FRANCISCO — Hewlett-Packard Co. has slapped ServiceNow Inc., a rival software firm, with a patent infringement suit.

Represented by Wilmer Cutler Pickering Hale and Dorr, HP sued San Diego-based ServiceNow on Thursday in the U.S. District Court for the Northern District of California. The Silicon Valley stalwart accuses ServiceNow of infringing eight patents in HP v. ServiceNow, 14-00570.