Apple iPhone 4s. Photo: Diego M. Radzinschi/ALM

A federal judge in San Jose has certified a class of iPhone 4 and iPhone 4S owners in California who, because of a software glitch, lost the ability to use the FaceTime feature to make video calls.

The lawsuit was filed in the wake of what U.S. District Judge Lucy Koh of the Northern District of California, who is overseeing the case, has termed the “FaceTime Break” after FaceTime stopped working on iPhone 4 and iPhone 4S devices that used iOS 6 or earlier operating systems in April 2014. Plaintiffs claim they were left with a catch 22 of either upgrading their operating systems with software their phones weren't equipped to run efficiently or to keep their existing software and lose the use of FaceTime.

Koh on Tuesday turned back arguments from Apple's lawyers at Kirkland & Ellis, who claimed the lawsuit was inappropriate for class treatment since owners of the old phones lost access to FaceTime for different amounts of time depending on how long they waited to upgrade their devices' operating system, and the plaintiffs varied in how much they actually used FaceTime.

But those arguments missed the thrust of the plaintiffs' case, Koh wrote.

“Plaintiffs' theory of the case is that Apple is liable because the FaceTime Break reduced the monetary value of class members' iPhones. Determining precisely how often a class member … used FaceTime is irrelevant to that analysis,” Koh wrote.

Apple representatives didn't immediately respond to a request for comment Wednesday.

The lawsuit came in the wake of an intellectual property setback for Apple. In November 2012, a federal jury in the Eastern District of Texas found one of the methods Apple used to connect FaceTime calls—using a so-called “peer-to-peer” connection—infringed patents owned by VirnetX Inc. After the verdict, Apple began connecting all FaceTime calls via a separate method using a third-party server to relay calls from device to device. But paying for the new method quickly ran up millions in fees for server space, according to internal Apple emails.

Apple hoped to cut those costs with the introduction of iOS7, but because of reported performance issues, users of old phones didn't upgrade new software en masse until the FaceTime Break.

The plaintiffs' damages expert claims the break caused prices of used iPhone 4 and iPhone 4S devices to fall by nearly 13 percent.

Plaintiffs, however, didn't get everything they asked for in Tuesday's order. Koh declined to certify a nationwide class to pursue claims of trespass to chattels under California law and claims under the state's Unfair Competition Law. Koh found that California choice of law rules precluded applying California law to the proposed nationwide class. She also denied the plaintiffs' request to certify a class to pursue injunctive relief finding that they hadn't spelled out just what relief they were seeking.

Also on Tuesday, Koh appointed Jill M. Manning of Steyer Lowenthal Boodrookas Alvarez & Smith, Daniel L. Warshaw of Pearson, Simon & Warshaw, John Austin Curry of Caldwell Cassady & Curry, and David F.E. Tejtel of Friedman Oster & Tejtel as class counsel.

Manning didn't immediately respond to a message seeking comment Wednesday.

Read the judge's ruling below:

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