eBay has filed suit to prevent Bidder's Edge from searching and displaying eBay's auction listings on the Bidder's Edge Web site, the company said.
"We believe that Bidder's Edge is engaging in the wholesale copying of our content and then using that content without our permission," said eBay spokesman Kevin Pursglove.
The suit comes after Bidder's Edge disclosed last month that it would resume searching eBay's auction listings. The auction service site previously had stopped these searches under threats from eBay.
The lawsuit also contends that Bidder's Edge violates eBay's copyrights and intellectual property.
"Bidder's Edge believes eBay's arguments are not justified, especially since the information eBay is trying to protect is not its own, but rather is data generated by eBay sellers," Bidder's Edge said in a statement.
Added Bidder's Edge chief executive James Carney: "The long-term implications of eBay's actions affect the entire industry. If eBay is successful, the value of the Web as an easily accessible and useful information source for consumers will be forever changed."
Bidder's Edge is not alone in this fight. AuctionWatch previously had another highly publicized battle with eBay.
Before the suit was filed against Bidder's Edge, eBay said it "disapproved" of the company's actions. It has been concerned that its users are not getting the full eBay experience through these outside sites.