In a far-reaching challenge to Amazon's online retail business, IBM has filed two patent infringement lawsuits against the online retailer, charging it with using business methods patented by IBM more than a decade ago. The lawsuits, filed in federal district court in Texas, take issue with Amazon.com's system for making customer recommendations, processing orders, storing data and other staples of e-commerce. "Amazon has built its business model on the use of IBM's patents, knowing its business was covered by and infringing IBM's patents," stated IBM in its complaint. IBM also alleged it first attempted to negotiate a licensing agreement with Amazon in 2002. "After four years of stonewalling, Amazon's intent is clear--Amazon would rather take IBM's property unlawfully than pay for its use," stated the lawsuit. Amazon did not respond to a request for comment.