DeNA confirmed today that it is acquiring ngmoco, creating the world’s largest mobile social games platform company. The price was $400 million in cash and securities, with ngmoco s shareholders and employees receiving $300 million, with up to a maximum of $100 million in bonuses contingent upon the achievement of certain performance milestones through the end of 2011.

“In ngmoco and its team we see a lot of the same talent and dynamic traction that we have in the Japanese market, making the merger a perfect fit for us,” said Tomoko Namba, founder and CEO, DeNA. “This acquisition cements DeNA’s leadership position in the U.S. We re building the largest mobile social gaming platform in the world and populating it with incredible games and services.”

ngmoco will work on making DeNA s Mobage a global service and platform for games. Ultimately, the company hopes to combine ngmoco s smartphone technology framework with DeNA s Mobage Open SDK in order to reach both Western and Japanese customers on iOS and Android.

“We are delighted to be joining forces with DeNA, a company that we have admired and aspired to,” said Neil Young, founder and CEO, ngmoco. “The opportunity to be a part of creating the number one social mobile game platform company and to benefit from the unique learning and knowledge that DeNA possesses is an amazing way to accelerate our vision for gaming.”