Amazon.com has filed a lawsuit against Cendant for patent infringement.
Amazon filed its lawsuit in federal court in Seattle on June 22, just two days after Cendant sued Amazon for infringing on its patents in a federal court in Delaware.
In its lawsuit, Amazon alleges that Cendant -- which owns a number of travel, hospitality and vehicle rental and real estate businesses, including Orbitz and Avis -- infringed on four Amazon patents. Those patents include its credit card number transmission methods and systems as well as its Internet-based customer referral methods and systems.
Amazon said it has "suffered and will continue to suffer irreparable injury and damages, in an amount not yet determined" for which it is entitled to relief. It is also seeking an injunction prohibiting Cendant from continuing to infringe on its patents.
In its initial lawsuit against Amazon, Cendant claimed that the online retailer infringed on its "system and method for providing recommendation of goods or services based on recorded purchasing history."
Cendant said that Amazon's online marketplace uses numerous features that recommend other goods to potential customers based on prior purchasing history. According to Cendant, those features, including "customers who bought this book also bought...," infringed on its patent.
Cendant is seeking a jury trial.