PALO ALTO, Calif.--June 21, 2006-- HP today announced that the company is working with national retailers Walgreen Co. and Office Max to resolve ink patent infringements found in multiple U.S. stores of both companies. Inks found in both Walgreens and Office Max refilling service stations infringe HP patents. Both companies are cooperating with HP and are working toward resolution. "HP protects its intellectual property wherever infringements are found," said Pradeep Jotwani, senior vice president, Supplies, Imaging and Printing Group, HP. "Decades of research and development investment by HP have resulted in more than 4,000 patents related to printing supplies, allowing us to deliver the superior quality and reliable printing experience associated with original HP supplies." The patent infringements were discovered as part of ongoing worldwide testing and enforcement efforts within HP that are designed to protect the company's intellectual property rights. Over the past year, the same initiative has uncovered ink patent infringements by other companies that offer generic ink supplies through refilling stations or private label brands.