Time Warner Inc's AOL has asked a federal court to rule that it is not infringing patents held by Yahoo Inc.

The request, in the form of a complaint seeking declaratory relief, cites an ongoing intellectual property dispute between Yahoo and Quigo, an online advertising company that AOL acquired for $340 million in 2007.

According to the complaint, attorneys for Yahoo have alleged in emails and letters sent over the past several years to AOL and Quigo that up to seven Yahoo patents are being infringed.

The parties' attempts to negotiate a settlement of the Yahoo defendants' patent infringement claims over several months until March 26, 2009, have been unsuccessful, read the complaint, filed on Tuesday in the U.S. District Court for the Southern District of New York.

AOL spokeswoman Allie Burns said the company does not comment on pending litigation. Representatives for Yahoo were not immediately available for comment.

AOL and Yahoo were in discussions about a potential combination last year, following Microsoft Corp's failed $47.5 billion bid to acquire Yahoo.

Yahoo Chief Executive Carol Bartz, who took the reins in January, recently met with Microsoft to discuss a partnership involving their search advertising business, according to a source familiar with the matter who spoke on condition of anonymity.

(Reporting by Alexei Oreskovic; Editing by Steve Orlofsky)

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