Google has won a victory in its battle against patent troll Rockstar, with a US District Court judge having denied Rockstar's request to try the case in the troll-friendly Eastern District of Texas, rather than in California.

Google, which is headquartered in Mountain View, California, filed suit against Rockstar in December and is seeking a declaration from the court that none of its products infringe on Rockstar's zombie Nortel patents.

Rockstar had asked the court to transfer the case to Texas on grounds that its subsidiary MobileStar, which owns some of the contested patents, has its principal place of business in that state, making it more convenient to call witnesses there. But in a ruling [PDF] issued on Thursday, District Judge Claudia Wilken of the Northern District of California questioned that claim.

"Indeed, Defendants have not identified any witnesses residing in Texas, their primary operations and headquarters are in Canada, and they admit that many of the inventors of the patents-in-suit were listed at least years ago as being from Canada," Judge Wilken wrote.

Wilken also rubbished the idea that MobileStar was a legitimate subsidiary company, observing that Rockstar created it and transferred thousands of patents to it just one day before it launched a barrage of lawsuits against tech companies – all of which, naturally, were filed in East Texas.

All MobileStar employees also work for Rockstar, she noted, and the company has just three officers, all of whom serve on Rockstar's board.

"The circumstances here strongly suggest that Rockstar formed MobileStar as a sham entity for the sole purpose of avoiding jurisdiction in all other fora except MobileStar's state of incorporation (Delaware) and claimed principal place of business (Texas)," Wilken wrote.

As such, she said, "the traditional notions of fair play and justice would not be offended" if the court considered Rockstar and MobileStar to be a single entity.

Moreover, because Apple is the majority shareholder in Rockstar and Rockstar's lawsuits have a "direct link" with Apple's unique business interests, Wilken wrote that it would not be unreasonable to try the issues in California, where Apple is also headquartered.

In all, it was a damning ruling for Rockstar, but certainly not the final one. Although Judge Wilken denied Rockstar's request to transfer the case to Texas, the full, ugly, interminable patent slugfest between Rockstar and Google is still to come. ®