It hasn't been a great couple of weeks for Zynga, whose less-than-stellar earnings report last Friday was quickly followed by allegations of insider trading by no fewer than five different law firms. Now, Electronic Arts and Maxis are piling on, suing Zynga over The Ville's similarities to EA's own The Sims Social.

EA believes that Zynga copied The Sims Social's game design, graphics, and other elements to such an extent that "the two games are, to an uninitiated observer, largely indistinguishable," said Maxis General Manager Lucy Bradshaw in a press release posted over at Joystiq. Bradshaw also wants to protect the "creative teams who feel that their hard work and imaginations have been ripped off" by the alleged copying.

For its part, Zynga intends to defend The Ville, which it says merely builds on innovations from earlier Ville titles, and General Counsel Reggie Davis said in a statement that it was "ironic that EA brings this suit shortly after launching SimCity Social which bears an uncanny resemblance to Zynga's CityVille game."

Zynga has been accused of lifting ideas from other games before—Zynga's Dream Heights and Zynga Bingo both share more than a passing resemblance with Nimblebit's Tiny Tower and Buffalo Studio's BINGO Blitz, respectively—but those relatively small studios often don't have the resources to respond through legal channels. In challenging Zynga over The Ville, EA also hopes to set a precedent that will protect the intellectual property of smaller developers whose ideas are being copied by Zynga and others. A recent New Jersey case involving Tetris clones did show that some basic game elements can be protected under copyright, but that the difference between a game that was copied wholesale from another and a game that was merely inspired by another is still difficult to distinguish in court.

The full complaint, which contains many more comparison images, can be found here.