A lawsuit filed by language software firm Rosetta Stone against Google for copyright infringement has been dismissed by a federal judge.

In its lawsuit, filed in July 2009, Rosetta Stone alleged that Google allowed third parties including individuals involved in software piracy to purchase the right to use Rosetta Stone trademarks or other terms confusingly similar in Google's Adwords advertising program.

Google said the ruling was "consistent with a growing line of decisions" about the Internet.

"Users searching on Google benefit from being able to choose from a variety of competing advertisers, and we've found no evidence that legitimate use of trademarks as keyword triggers or in the text of advertisements confuses consumers. We're pleased that the judge has ruled in Google's favor, consistent with a growing line of decisions in the Internet space," Google said in a statement.

Rosetta Stone expressed its disappointment about the ruling, charging that Google does not do enough to stop such practices on its AdWords platform.

"We are deeply disappointed that Rosetta Stone was not given an opportunity to present at a public trial the facts underlying Google's practices and the motivation that led Google to adopt its current trademark policies," stated Tom Adams, President and CEO of Rosetta Stone Inc.

"Google has a corporate responsibility to protect consumers and promote trust in its search results. Without question, Google knows that counterfeit software is being advertised in its Adwords program and takes no effective steps to stop this illicit activity."

Rosetta Stone said it plans to review the decision and will consider an appeal to the U.S. Court of Appeals.