Online classifieds leader filed a countersuit on Tuesday against business rival eBay, accusing the company of using its minority stake in Craigslist to gain access to trade secrets.

In a lawsuit filed in California Superior Court in San Francisco, Craigslist said eBay gathered proprietary information about the business and illegally diverted Internet traffic to a competing site owned by eBay.

In April eBay sued Craiglist, claiming that it was challenging recent transactions implemented by craigslist's board of directors, consisting of Craig Newmark and Jim Buckmaster which unfairly diluted its interest in the site after it developed a rival offering called Kijiji.

EBay introduced Kijiji classifieds in the U.S. on June 29, 2007, and Craigslist notified eBay that this constituted direct competition, resulting in the loss of some eBay rights.

The latest lawsuit asks for unspecified damages, and a court order that would force eBay to return all shares of Craigslist that were acquired by means of unfair competition.

San-Jose based Ebay bought a minority ownership stake in Craigslist nearly four years ago as part of a strategy to buy up classified advertising services both in the United States and Europe.