The move highlighted Shanda's ambitions abroad. Shanda also has plans with local operators to offer six of its games in the U.S., said Diana Li, CEO of Shanda Games, in a phone interview. Li declined to name the games but said they would keep the free-to-play model they have used in China. By contrast, many U.S. games rely on subscription fees for revenue and do not sell in-game items for real cash.

Shanda's popular titles include fantasy role-playing games World of Legend and Legend of Mir. Shanda is also looking at offering games in Europe, Li said.

Shanda rival Perfect World has already launched several games in the U.S. and offers them under altered names including Jade Dynasty and Ether Saga. Changyou late last year started open beta testing in the U.S. for Dragon Oath, a martial arts game.

A big challenge for the Chinese companies could be promoting their games in the U.S., and games closely linked to Chinese culture or history may not do well, said Natkin of Marbridge Consulting.

"There are certain cultural themes that just never seem to get old for that culture... but they won't find as big a market overseas," said Natkin. Users in the U.S. also may not take well to the cute, cartoon-like animation popular in some Chinese casual games, Natkin said.