US Report: HP's Tit-for-tat lawsuit hits Xerox

HP has also asked the U.S. District Court in San Francisco for a permanent injunction, barring Xerox from using any of the technology in its copiers. The suit comes just two weeks after Xerox filed a patent suit of its own against HP. That suit accuses HP of violating Xerox patents related to ink-jet printers.

HP officials said the suit was not filed in retaliation. "Their case caused us to review our patents vs. their product portfolio, and we discovered their unauthorised use of our technology," said an HP spokeswoman. "We believe their suit is without merit and we were surprised by it."

HP's suit involves a patent titled "Touch-screen two-dimensional emulation of three-dimensional objects." HP has asked for an injunction against Xerox's production of the Document Centre 220, 230 and 265 copiers, the 5799, 5800 and 5855 models, and the DocuColor 40 copier, the spokeswoman said.

HP is also seeking unspecified damages. Xerox officials said they hadn't yet seen the complaint and had no comment.