Updated

Yahoo is suing Facebook for patent infringement -- and the people responsible for Yahoo’s patents are outraged.

Andy Baio sold Upcoming.org to Yahoo in 2005 for an undisclosed sum, and agreed at the time to help the company file for patents based on the site he had invented and the code he had written. Baio was hesitant to do so, but told Wired.com that he thought he was helping as a precautionary measure.

“I thought I was giving them a shield,” Baio said. “It turns out I gave them a missile with my name permanently engraved on it.”

He helped Yahoo file for eight patents, four of which were later granted. And while none were cited in the Yahoo complaint, Baio said a handful were now “weaponized to use against people like me.”

[summary]

More On This...

Patent lawsuits have become a driving force in technology recently; Apple has been seeking to ensure its dominance of the tablet market by suing rival Samsung, citing patent infringement in more than 30 cases across 10 countries. And Microsoft has been using its patent portfolio as a source of revenues, ironically earning profits for every gadget that its competitors sell.

“Yahoo assured us that their patent portfolio was a precautionary measure, to defend against patent trolls and others who might try to attack Yahoo with their own holdings,” Baio said. Instead the tech landscape has turned into a cold war where patents are stockpiled rather than nuclear arms -- “and every company in the valley had a bunker full of them,” he told Wired.

Other inventors and entrepreneurs tell a similar story.

Paul Graham sold his company Viaweb to Yahoo in 1998 for $49 million. He told CNET in no uncertain terms that he thinks the lawsuit was a mistake.

"This was a clumsy move that will blow up in Yahoo's face," he wrote in an e-mail. "The biggest priorities for any tech company right now is hiring, and this is going to make it impossible for them to hire good people."

[pullquote]

And Marc Cuban, the Internet entrepreneur who sold broadcast.com to Yahoo for more than $5 billion in 1999, spoke his mind about the lawsuit in a blog post Tuesday sarcastically titled “I Hope Yahoo Crushes Facebook .”

“I hope Yahoo is awarded 50 billion dollars,” Cuban wrote. “It is the only way that consumers will realize what is at stake with patent law as is.”

Yahoo filed the lawsuit against Facebook on Monday, accusing the social network of infringing on ten patents covering advertising, privacy, and social networking in general.  It comes mere weeks before Facebook is set to cash in on what is widely expected to be among the biggest IPOs ever.

"We're disappointed that Yahoo, a longtime business partner of Facebook and a company that has substantially benefited from its association with Facebook, has decided to resort to litigation,” a Facebook spokesman told Foxnews.com.

“Once again, we learned of Yahoo's decision simultaneously with the media.  We will defend ourselves vigorously against these puzzling actions."

Yahoo did not immediately respond to FoxNews.com requests for reaction.