Patent troll stalks travel site Hipmunk

Hipmunk’s quest to “take the agony out of travel planning” has won plaudits from users and the media and earned the start-up a new $15 million investment. Now, a patent troll wants Hipmunk to give it a piece of the action.
Just days after Hipmunk’s June funding announcement, a company called i2z Technology LLC told the travel start-up that it has to buy a license for a 1994 patent that covers a method for displaying data in multiple computer windows.
Despite its high-tech sounding name, i2z is simply a Texas shell company run by a California lawyer that is targeting internet and travel companies including Kayak, Google (s goog), Yelp (s yelp) and Microsoft (s msft). Under i2z’s business model, known as patent trolling, firms that don’t make anything collect patents in order to extract licensing settlements from companies that do.
In a new twist, trolls have begun laying in wait for start-ups to receive funding before pouncing. That is what happened to hand-crafted goods marketplace Etsy earlier this year.
In an attempt to fight the troll, Hipmunk has taken pre-emptive action by filing a lawsuit asking a federal judge in San Francisco to declare that it’s not infringing the patent and that the patent should be invalidated because it’s obvious.
Hipmunk’s complaint notes that this is the second time it has been threatened by a patent troll this year and that the patent has nothing to do with Hipmunk’s technology. It adds:

Though its funding is intended for innovation, Hipmunk elects to defend its technology rather than spend its hard-earned venture capital paying for a license it does not need.

The patent in question is US Patent¬†5,345,551, “method and system for synchronizing the presentation of data from different, but related, sources in different windows of a computer display”. Like many patents related to software, it covers seemingly common-place internet functions.
More details can be found in Hipmunk’s complaint here:
Hipmunk v Patent Troll