he filing is the latest skirmish in an eight-month-long saga, during which Okada and Wynn have also sued each other in the United States.
Representatives for Wynn were not immediately available. Universal, in a stock exchange statement, said it had filed the lawsuit before the Tokyo District Court.
Until this past winter, Okada was the largest shareholder in Wynn's us$ 11 billion gambling empire, which has casinos in Las Vegas and Macau. He helped bankroll Wynn's operations for more than a decade.
The two fell out publicly in January when Okada filed a lawsuit in the U.S. against Wynn for blocking access to financial documents relating to a us$ 135 million company donation to the University of Macau.
Wynn stripped Okada of his once 20 percent share holding in Wynn Resorts through Okada's US subsidiary Aruze, claiming he was unsuitable to continue as a board member of the company after an internal investigation by former FBI Director Louis Freeh alleged Okada had violated U.S. anti-corruption laws.
Both self-made billionaires claim the other made improper payments to win favour in their respective Macau and Philippines markets. "We have not yet seen any documents relating to a filing by Okada in Japan, however we assume this is another attempt to distract from the real issues facing Aruze and Okada as identified in the Freeh Report," a spokesman for Wynn said in an email.
Okada who made his fortune in pachinko - a game that is a cross between pinball and slots - is developing a us$ 2 billion casino resort in the Philippines. He has denied his company has done anything improper to obtain government favours.