Apple is suing Amazon over the use of the term 'app store' in its new online store for mobile applications.
Apple filed papers in court at the end of last week, and called on Amazon to stop using the name and pay damages for improper use of the trademark, according to reports.
Amazon's Appstore for Android went live today in the US and is expected to launch in the UK next week. However, the company has been using the term to describe a developer eco-system for some time.
Apple has released a short statement staking its claim on the term, and suggesting that Amazon is misleading customers.
"We've asked Amazon not to copy the App Store name because it will confuse and mislead customers," Apple said in a statement released to V3.co.uk.
Amazon, however, uses the term 'Appstore' to describe its services, which could be enough to counter claims about unfair use.
Microsoft has also challenged the validity of Apple's claims on the words, arguing that the term 'app store' is too generic for one firm to own.
In January, Russell Pangborn, associate general counsel for trademarks at Microsoft, said in a statement: "The term 'app store' should continue to be available for use by all without fear of reprisal by Apple."
Apple countered that Microsoft's filing was weak.
Amazon has not responded to calls for a response to Apple's legal action, but the two companies are increasingly competing in similar markets.
Both have stepped into the e-book market, and both offer customers a range of digital downloads such as music.
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