Digital music player maker Creative Technology has asked a US court to ban Apple from selling or marketing its iconic iPods in the US.
Creative has been struggling to keep up with market leader Apple
Creative claims that the navigational menu used for finding and playing music on the iPod, violates its patent for its own Zen MP3 player.
It applied for the patent in 2001 which was granted in August 2005.
Since then it has been threatening legal action. The complaint was lodged at the San Francisco district court.
Import laws breach?
Last year Creative boss Sim Wong Hoo told the BBC he planned to "pursue aggressively" the US patent.
Through the court it is seeking an injunction and increased damages for what it says is a "wilful infringement of the Zen patent".
Creative said it had also filed a complaint to the US International Trade Commission, asking it to investigate whether Apple had breached import laws by selling iPods and the iPod Nano.
Apple's iPod continues to be fantastically popular
It claimed it had met with Apple CEO Steve Jobs and other representatives in 2001 to discuss ways the two companies to work together but had rejected Apple's proposals.
Nobody from Apple would comment on the legal action.
Creative has struggled against the market dominance of the iPod and earlier this month plunged into the red.
It blamed its $114m (£62m) losses for the three months to March on the plunge in MP3 player prices and its need to get rid of stock.
But it pledged to return to profit in the second half of 2006, saying it was renewing its focus on high-margin products, such as computer sound cards.
Apple launched the iPod in 2001 and now has 72% of the US portable MP3 player market while Creative has less than 10%, according to research group NPD.