Playing with dolls might be for children, but Barbie’s attorneys are dragging Bratz to the not-so-friendly playhouse of federal court.

In a four-year legal battle with billions of dollars at stake, Mattel Inc. alleges that a doll designer took his drawings for the Bratz line when he left Mattel and accepted a job at MGA Entertainment eight years ago and gave them to his new employer. The suit is scheduled for a federal jury trial on May 27.

A verdict in favor of Mattel could result in damages of up to $360 million against Van Nuys-based MGA and could cripple the company if it were stripped of its $2 billion marquee product.

As the case nears trial, the judge’s rulings have been going in Mattel’s favor.

Mattel lawyer John Quinn, of Los Angeles-based Quinn Emanuel Urquhart Oliver & Hedges LLP, will try to convince a jury that the designer, Carter Bryant, did drawings of the Bratz dolls, complete with their distinctive almond-shaped eyes and oversized sneakers, while working at Mattel. He will also claim an agreement Bryant signed with Mattel gives the El Segundo toy giant the rights to those sketches.

“It will be interesting if MGA loses the intellectual property of Bratz,” said Jim Silver, editor-in-chief of trade publication Toys and Family Entertainment and a toy industry expert. “If Mattel wins, it really comes down to what kind of damages MGA owes, and any way you cut it, we are talking about sales in the billions of dollars.”

If a jury agrees that Mattel owns the copyright to Bratz, the company could recover lost profits and $500 million in annual sales and licensing fees. And Mattel could ask for a permanent injunction against MGA, stopping the company from selling the Bratz line, said Michelle Cooke, an intellectual property lawyer in the Los Angeles office of Steptoe & Johnson LLP who is not involved in the case.

But it might be in Mattel’s interest to work out an arrangement under which Mattel would benefit from MGA’s production of Bratz dolls.

“Mattel may be able to get an ongoing licensing agreement with MGA, which could be a win-win situation for Mattel given the decline in Barbie revenues,” Cooke said.

Cooke was referring to the decline of the empire of Barbie, who made her debut in 1959. Barbie has been dressed by such fashion icons as Bob Mackie and Donna Karan, and has served as a girls’ role model by working as a doctor and an astronaut. Sales of the smiling blonde, however, have gone into a downturn in recent years.

In an April conference call to investors, Mattel Chief Financial Officer Kevin Farr said U.S. Barbie sales fell in the first quarter by 12 percent.

Bratz sales haven’t been spectacular lately, either, losing ground to Disney’s new dolls based on Hannah Montana and the popular High School Musical franchise.

“Bratz is a huge money maker, but it is not at the level it once was,” Silver said. “They have fallen off in the last 15 months because of the success of Hannah Montana and High School Musical dolls.”