California - Real estate information website operator Zillow Inc. sued its rival Trulia Inc. in Seattle federal court Wednesday accusing Trulia of infringing its patent for an automated method of determining a home's value based on user input.
"Trulia's blatant and ongoing copying of Zillow's innovative approach to
home valuation infringes Zillow's patent and Zillow is entitled to damages and an injunction against further infringement," Zillow's complaint in the Western District of Washington says.
Zillow.com launched in 2006, "revolutionizing the industry" by offering users the patented Zestimate home valuation service, according to the complaint.
The Zillow Zestimate allows home owners and real estate professionals to update automatic valuations of homes with additional home facts and information to refine the valuation. Over 33 million homes have been valued in this way, out of Zillow's database of over 100 million homes, which makes the Zillow database substantially more useful and accurate for users, Zillow says.
Zillow applied for a patent in February 2006 for its process for using users' data input to refine its automatic home valuations. U.S. Patent Number 7,970,674 issued in June 2011, titled "Automatically determining a current value for a real estate property, such as a home, that is tailored to input from a human user, such as its owner."
Trulia runs another real estate information website, Trulia.com, and offers mobile applications for smartphones and tablets, all of which compete with Zillow for web traffic and revenue, according to Zillow.
In September 2011 Trulia announced that it would start providing automatic home valuations using homeowner input to refine those valuations, calling its product "Trulia Estimates."
Like Zestimates, Trulia Estimates provide automatic valuations of properties based on recent sales of similar homes and home facts like number of bedrooms and bathrooms, square footage, and other factors. Trulia Estimates also permits and relies on homeowners to claim their home and provide additional information about their properties to refine the automatic valuations.
When Trulia first launched Trulia Estimates, it was obvious to commentators that Trulia was merely copying Zillow, Zillow claims. Commentators accused Trulia of being a "copycat" of Zillow's Zestimate service and predicted that Trulia's copycat version might "ding" Zillow's web traffic, the company said.