SAN FRANCISCO — A federal judge has refused to shield a self-described troll fighter from a legal offensive waged by a descendant of the original patent troll.

In a 30-page order issued Tuesday, U.S. District Judge Yvonne Gonzalez Rogers of the Northern District of California rejected RPX Corp.’s motion to dismiss claims that it conspired with leading Android manufacturers to boycott patents held by Cascades Computer Innovation, a nonpracticing entity.