Apple is headed to court today to defend against allegations that it “abused a monopoly position in the digital music player market”, in a class action lawsuit in California that could cost the company $1 billion, reports Reuters.

The case in question was brought forward by a group of businesses and individuals who bought iPods between 2006 and 2009, who claim that a 2006 iTunes software update locked music purchased on iTunes so that it could only be played on Apple’s portable music players.

The update also barred RealPlayer music from iPods, which posed a problem for those who owned RealPlayer content, and that discouraged plaintiffs from upgrading to a competing device.

To put it more simply, those who bought music on iTunes and RealPlayer wouldn’t be able to listen to RealPlayer content on their iPods, and switching to a different device would lock them out of their iTunes libraries.

The group is seeking $350 million in damages, which, under antitrust laws, automatically triples to over $1 billion.

Apple says that its iTunes software update included genuine product improvements and shouldn’t be construed as anti-competitive.

Emails and taped deposition excerpts from the late Apple co-founder Steve Jobs are expected to be entered into evidence, and top executives Eddy Cue and Philip Schiller are scheduled to testify at Tuesday’s trial in Oakland.

➤ Apple heads to trial over digital music claims [Reuters]

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