Apple's effort to trademark the name "App Store" has run in to opposition from Microsoft, which argues the phrase is too generic to register and would restrict competitors' ability to use of the term to describe their own services.

A week after Apple launched its App Store for iPhone apps in 2008, the company applied for a trademark for "app store," a retail store offering "services featuring computer software provided via the internet and other computer and electronic communication networks," as well as other services, according to its application with the U.S. Patent and Trademark Office.

However, Microsoft filed a motion yesterday opposing the application with the agency's Trademark Trial and Appeal Board, saying "app store" is "generic for retail store services featuring apps and unregistrable for ancillary services such as searching for and downloading apps from such stores." Microsoft argued that "app" is a common term for mobile software applications, and that "store" is a common term for a "place where goods are sold."