Apple applied for the trademark in 2008 for goods and services including "retail store services featuring computer software provided via the internet and other computer and electronic communication networks" and other related offerings.
Apple launched its App Store for the iPhone that year along with its iPhone 3G. The store is now available on any device that runs the company's iOS software, namely the iPod Touch and iPad, and Apple introduced its Mac App Store earlier this month.
On Tuesday, Microsoft filed a motion for summary judgment with the agency's Trademark Trial and Appeal Board, asking it to deny the trademark to Apple. The status page for Apple's trademark request says "an opposition is now pending" at the trial board. The Seattle-based news site TechFlashPodcast reported on Microsoft's filing on Tuesday and provided a link to Microsoft's filing.
In its motion, Microsoft said "app" is a generic term for what is sold at the App Store and that "store" is generic for retail store services. Apple's archrival also attempted to use CEO Steve Jobs' own words against him, citing a published interview that quoted Jobs as saying "Amazon, Verizon and Vodafone have all announced that they are creating their own app stores for Android".
Microsoft also said consumers and the trade and general media use "app store" generically to mean online stores where applications are sold.
"'App store' is a generic name that Apple should not be permitted to usurp for its exclusive use. Competitors should be free to use 'app store' to identify their own stores and the services offered in conjunction with those stores," Microsoft said.
Apple's online store represented a new idea for mobile software shopping when it was launched and quickly became a big success, emulated by many other handset makers and some mobile operators.
Microsoft launched an online store for applications to run on Windows Phone 7 devices after that platform went on sale late last year. In December, research company IDC said Microsoft's store had reached 4,000 available applications in just two months. That growth compared favorably with the expansion of offerings in the Apple and Android mobile software stores during comparable times in their history, IDC said.