Microsoft is fighting rival Apple's claim that it has dibs on the name "App Store," arguing the term is generic and can be used by any shop selling programs for gadgets such as smartphones.
Microsoft has asked the US Patent and Trademark Office to deny Apple's request to "exclusively appropriate" the term "app store" based on the success of the iPhone, iPod and iPad maker's online software shop bearing that name.
"The undisputed evidence shows that 'app store' is a generic name for a store offering apps," Microsoft lawyer William Ferron Jr. said in a filing this week with the trademark office.
"Apple cannot leverage its early success to prevent competitors from using this generic term for their own app stores."
Microsoft called for the the rejection of Apple's request to register "App Store" as a trademark.
Even Apple chief executive Steve Jobs has publicly referred to rival software shops as app stores, according to Ferron.
California-based Apple launched its App Store in 2008 as a shop for fun, hip or functional mini-programs for its trend-setting mobile gadgets.
The success of the shop, and its role in making Apple devices marketplace hits, has prompted Internet titan Google and a slew of mobile phone makers to launch apps stores of their own.
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