EA said Friday that "The Ville" is "unmistakable" in its similarity to "The Sims Social," which launched more than a year earlier. EA says the games are "largely indistinguishable" to a casual observer.
"The similarities go well beyond any superficial resemblance. Zynga's design choices, animations, visual arrangements and character motions and actions have been directly lifted from The Sims Social," said Lucy Bradshaw, general manager of EA's Maxis Label, which developed the game, in a blog post Friday.
The games are both played on Facebook. Players create characters who live, work and interact with each other in virtual neighborhoods.
In response, Zynga says that EA doesn't understand copyright principles, and that it plans to defend its rights.
"It's also ironic that EA brings this suit shortly after launching SimCity Social which bears an uncanny resemblance to Zynga's CityVille game," said Reggie Davis, Zynga's general counsel, in a statement.
The lawsuit was filed Friday in U.S. District Court for the Northern District of California.
Shares of EA, which is based in Redwood City, California, rose 56 cents, or 5 percent, to $11.93 amid a broader market rally. The stock has traded in the 52-week range of $10.77 and $26.13.
San Francisco-based Zynga's stock rose 9 cents, or 3.3 percent, to 2.79 in afternoon trading. The stock is down 72 percent from its $10 initial public stock offering price. The company went public in December.