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Allen's now-defunct company, Interval Licensing, is suing Apple, Google, Facebook, Yahoo and seven other firms, accusing them of infringing on four of its patents related to Internet search and e-commerce.

According to the suit, Interval is asking for an injunction against the companies to prevent further infringement.

"This lawsuit is necessary to protect our investment in innovation," David Postman, a spokesman for Allen, said in a statement.

Patent lawsuits have become controversial in the tech industry with the rise of so-called patent trolls, which amass patents but then don't make any products with them, instead taking companies to court for violations that can result in big settlements. Tech firms such as Intel and Apple have supported comprehensive rule changes that would stem such patent lawsuits, but Congress has not taken up the issue.

In July, Virginia-based NTP sued Google, Microsoft and Apple alleging patent violation. NTP holds patents but does not make any products.

Interval took pains in its news release to emphasize that it not only owns the patents in question but developed them, too - heading off criticism that it is a patent troll taking advantage of other companies' innovations.

"Interval Research was an early, ground-breaking contributor to the development of the internet economy," Postman said in the statement. "Interval has worked hard to bring its technologies to market through spinning off new companies, technology transfer arrangements, and sales of its patented technology."

The patents named in the suit cover technology that would sound familiar to many Internet users. One lets people see peripheral content while they're focused on something else. Another feeds users' suggestions for related content - say, a product they might want to buy.

The other companies named in the suit include AOL, eBay, Netflix, YouTube, Staples, Office Depot and OfficeMax. Two big names, however, were missing from the list: Microsoft and Amazon.

Facebook and eBay both vowed to fight back.

"We believe this suit is completely without merit and we will fight it vigorously," Facebook said in a statement.

Google decried the rise of patent lawsuits.

"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 said in a statement. "Innovation - not litigation - is the way to bring to market the kinds of products and services that benefit millions of people around the world."

AOL said it would not comment on the lawsuit. Netflix, Staples, Office Depot and OfficeMax did not respond to requests for comment.

Allen founded Microsoft with his childhood friend Bill Gates in 1975. He served on the company's board until 2000. He was diagnosed last year with non-Hodgkin's lymphoma. In July, Allen said he was leaving most of his estate to philanthropy.