The claim is part of a March 2011 trademark lawsuit in which Apple, which this year became the world's largest company ever by market value, accused Amazon of misusing its "App Store" name to solicit developers for a mobile software download service.

Apple added the trademark claim last November, soon after Amazon announced the launch of the Kindle Fire tablet and, according to the complaint, began to call its app store "Amazon Appstore" rather than "Amazon Appstore for Android." It said this change could have contributed to confusion among consumers.

But in a filing on Wednesday with the U.S. District Court in Oakland, California, Amazon said the term "app store" has become so generic that its use could not constitute false advertising.

Amazon added that even Apple Chief Executive Tim Cook and his predecessor Steve Jobs have used the term to discuss rivals, with Cook having commented on "the number of app stores out there" and Jobs referring to the "four app stores on Android."

"Apple presumably does not contend that its past and current CEOs made false statements regarding to those other app stores to thousands of investors in earnings calls," Amazon said.

"To the contrary, the use of the term 'app store' to refer to stores selling apps is commonplace in the industry."

Kristin Huguet, an Apple spokeswoman, declined to comment.

Apple is based in Cupertino, California, and Amazon in Seattle. A hearing on Amazon's motion is scheduled for October 31, and a trial is scheduled for August 19, 2013.

The case is Apple Inc v. Amazon.com Inc et al, U.S. District Court, Northern District of California, No. 11-01327.

(Editing by Edwina Gibbs)

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