A US firm owned by billionaire Microsoft co-founder Paul Allen has filed a lawsuit against 11 web-based companies including Apple, Facebook, Yahoo!, Google, and YouTube on charges of patent infringement.
Interval Licensing said the firms were violating patents on fundamental web technologies the company developed in the 1990s.
"Interval Research was an early, ground-breaking contributor to the development of the Internet economy," David Postman, a spokesman for Allen, said.
"This lawsuit is necessary to protect our investment in innovation."
Postman said the technology at issue in the lawsuit, filed in a Washington court on Friday, was created by Interval Research, a company founded by Allen and David Liddle in 1992.
Four patents related to Web search, multimedia, screen pop-ups and database management were allegedly violated.
The list of defendants in the lawsuit included AOL and Internet auction house eBay.
"We believe this suit is completely without merit and we will fight it vigorously," Facebook said in a statement responding to the complaint.
Google also slammed the lawsuit.
"This lawsuit against some of America's most innovative companies reflects an unfortunate trend of people trying to compete in the courtroom instead of the marketplace," a Google spokesman told the AFP news agency.
Microsoft, which Allen founded with Bill Gates in 1975, was not named in the suit.