Apple's lawyers late Wednesday night sent a letter to the federal judge overseeing the jury trial, saying the company had concluded that an iPod owned by Marianna Rosen of New Jersey, one of two named plaintiffs, was not relevant to the case's time period.
Apple is accused of using a copyright management system in its music software to block songs from competing music stores from being played on the iPod.
The class action seeks damages for iPods bought from September 2006 to March 2009. Apple said it checked the serial number of Rosen's iPod Touch and found that it was bought in July 2009, months after the class period ended.
Apple's lawyers also said the company could not verify purchases of other iPods that Rosen said she had bought, including an iPod Nano in the fall of 2007. Apple lawyers said they had requested proof from Rosen's lawyers of her purchases.
Apple also said it had asked the plaintiffs' lawyers for proof of any purchases of iPods by the other plaintiff in the case, Melanie Tucker of North Carolina. Apple said it verified that an iPod Touch was purchased by Tucker in August 2010, also outside the class period. In her testimony, Tucker said she bought an iPod in April 2005.
The judge overseeing the case, Yvonne Gonzales Rogers, said she was concerned about the potential issues presented by the letter.
"I am concerned that I don't have a plaintiff," she said. "That's a problem."
Gonzales Rogers said she would independently research the matter, but she told both sides she wanted to address the issue quickly. If there are no plaintiffs, the trial could be stalled indefinitely or halted.
The plaintiffs' lawyer, Bonny Sweeney, said her team had not yet reviewed documentation to respond to Apple's lawyers because the letter had been sent so late.
Thursday morning, two of Apple's top executives, Philip W. Schiller, its head of marketing, and Eddy Cue, who oversees iTunes and Apple's other online services, testified about the copyright management system.
Cue, who was involved in the early negotiations for iTunes music, said the music companies had already been running their own digital music stores that used copyright protection, and they wanted Apple to adopt a similar system.
Even when Apple agreed to use copyright management, it still had to push hard to get music companies on board with iTunes, Cue said. The key to winning them over was telling them that the iTunes Store would be available only for Macintosh users in the United States - a tiny population at the time.
Schiller emphasized that the iPod was designed to work with one type of software to manage it, iTunes. This ensured that the product worked smoothly with its software and music store.
"If there were multiple management pieces of software trying to do the same thing, it's like having two steering wheels in a car," Schiller said.
Schiller pointed to Microsoft as proof that Apple was right in its iPod design. Microsoft had long marketed its own products as being more "open" than Apple's proprietary systems. But when Microsoft released its Zune music player in 2006, it adopted a system similar to Apple's, he said.
A videotaped deposition by Steve Jobs, the chief executive of Apple who died in 2011, will be the next major evidence presented in the case.
© 2014 New York Times News Service
For the latest tech news and reviews, follow Gadgets 360 on X, Facebook, WhatsApp, Threads and Google News. For the latest videos on gadgets and tech, subscribe to our YouTube channel. If you want to know everything about top influencers, follow our in-house Who'sThat360 on Instagram and YouTube.