Apple has sued Amazon.com, saying the online retailer is using Apple’s “App Store” trademark for a mobile-software developer program, reports “Bloomberg” (http://macte.ch/c5tsj).

In a complaint filed March 18 in federal court in northern California, Apple accused Amazon.com of trademark infringement and unfair competition and asked for a judge’s order to prevent the company from using the “App Store” name, as well as for unspecified damages.

Apple registered for a trademark on the term App Store on July 17, 2008. It has been using the name since then to refer to its applications store for iOS devices. Earlier this year it also launched the Mac App Store.

“Amazon has begun improperly using Apple’s App Store mark in connection with Amazon’s mobile-software developer program,” Apple said in the complaint. Amazon also plans to use the name with a mobile-software download service, the complaint states.

Amazon began using the App Store designation around the beginning of this year, according to the lawsuit. “Amazon has unlawfully used the App Store mark to solicit software developers throughout the United States,” Apple claimed in its suit.

In the court filing, Apple said in the court filing that it contacted Amazon three times to demand that it cease using the name and that Amazon hadn’t “provided a substantive response.” “We have a long-standing practice of not commenting on pending litigation,” Mary Osako, a spokeswoman for Seattle-based Amazon, told “Bloomberg” on Monday.

Apple’s lawsuit against Amazon comes as the online retailer is reportedly preparing to launch an online store to distribute apps for devices that run on Android.

Meanwhile, Apple is in a similar battle with Microsoft. The latter argues that merely combining the word “store” with the word “app” — which is nothing more than a short term for “application,” a term that can describe any software program — shouldn’t qualify for a trademark. That legal brouhaha is being decided by a special board in the U.S. Patent and Trademark Office.