Judge Laura Taylor Swain

In his 2011 patent infringement suit, Williamson's Feb. 12, 2012, contentions accused AT&T's U-verse product of including video hub offices "VHOs [that] … insert local television stations or community programs." Gleaning information from AT&T's production of 1.8 million pages of documents—and deposition of its Rule 30(b)(6) witness Chase—Williamson sought to amend his infringement contentions to incorporate 32 previously unavailable facts about the U-verse product, including that "local advertising is inserted in national multicast content in the VHOs." Finding that he did not show that he exercised diligence in accusing U-verse's local ad insertion technology, district court—discussing the Norther District of California's Patent Local Rules—denied Williamson's motion to amend his infringement claims. A magistrate observed, in July 2012, that AT&T's insertion of local advertisements into its broadcast/delivery content was open and notorious to anyone using a TV connected to the AT&T network. Further, when Williamson served his preliminary infringement contentions, vendor BigBand Media had already disclosed—in June 2005—a detailed description of the mechanism of local ad insertion via its Media Services Platform.