Xerox has filed a lawsuit against Yahoo, Google and YouTube alleging infringement of Xerox patents on search and integration technology.
The document management and services company alleges that Google's AdWords and AdSense services violate a Xerox patent on automatically generating searches. The suit, filed Friday in U.S. District Court for the District of Delaware, also alleges that Yahoo Search Marketing, Yahoo Publisher Network and Y!Q Contextual Search infringe the patent.
Xerox also alleges that the Google Maps, Google Video and Yahoo Shopping services all infringe another Xerox patent on ways to integrate information from different sources. Online video site YouTube.com infringes the same patent, Xerox alleges.
Google and Yahoo could not immediately be contacted for comment, but the companies were cited by The Wall Street Journal as saying they intend to fight the charges.
The lawsuit adds to a set of ongoing legal battles among tech companies over patents. The U.S. International Trade Commission is investigating patent violation complaints brought between Apple and mobile phone maker Nokia. The commission is also investigating a patent complaint filed by Kodak against Apple and Research In Motion, the maker of the BlackBerry.
(Stephen Lawson in San Francisco contributed to this story.)