NEW YORK (CNNMoney) -- Apple has been dealt a blow in its "App Store" trademark case, with a federal judge denying its request for an injunction to stop Amazon from using the term.
Apple (AAPL, Fortune 500) filed a lawsuit against Amazon in March, saying that it has used the term "App Store" since 2008 and applied for a trademark at that time. Apple argued that Amazon's "Appstore," an Android marketplace that launched in March, infringes on the trademark and is confusing to customers.
Amazon (AMZN, Fortune 500) fired back, saying the mark is generic and therefore not protectable -- and even if it weren't generic, Apple "cannot demonstrate any likelihood of confusion."
Judge Phyllis Hamilton mostly sided with Amazon in her ruling on Wednesday in California district court, in which she denied Apple the injunction it sought.
Hamilton wrote that she "does not agree with Amazon that the mark is purely generic," but also said that "there appears to be no need for a leap of imagination to understand what the term means."
Apple failed to prove its main points, she said, including: that Amazon's "Appstore" name will confuse customers, that it infringes on Apple and that it dilutes Apple's brand.
In a twist of the knife, Hamilton seemed to imply that Apple could have won the case if it had better protected the phrase in question.
"Apple did have substantially exclusive use of 'App Store' when it launched its service a little over three years ago, but the term appears to have been used more widely by other companies as time has passed," she wrote.
Apple spokewoman Kristin Huguet pointed back to an earlier company statement on the case: "We asked Amazon not to copy the 'App Store' name because it will confuse and mislead customers," she said.
Amazon did not immediately respond to a request for comment.
Apple announced Wednesday that more than 15 billion apps have been downloaded from its App Store. 
