Xerox Corp has filed a patent infringement suit against Mita Copystar America Inc, the US subsidiary of Japanese-based copier and printer company Mita Industrial Co Ltd, claiming that Xerox- patented technology is contained in a number of Mita products. The suit contends that certain Mita products violate four separate patents held by Xerox and seeks an injunction forcing Mita to stop selling the disputed products, as well as unspecified damages. The products in question were not specified in the initial complaint filed with the court. Xerox, which has said it plans to defend its intellectual property more vigorously than it has in the past, filed a similar suit against Hewlett- Packard Co in May, claiming infringement of its technology patents by certain HP ink-jet printers and related supplies. HP struck back with a suit of its own later that month, claiming that Xerox was illegally using touch screen user interface technology that it had been granted a patent for. Xerox claims to have invested, along with its Fuji Xerox venture, $1.7bn in research and development last year alone and says it was awarded almost 800 patents.