A lawsuit has been filed by Kazuo Okada, the biggest shareholder in Wynn Resorts, against the US-based operator in which he alleges the company has refused to allow him to see its books.

Filed in the District Court of Clark County, Nevada, the lawsuit states that despite several written demands, Wynn Resorts insists on keeping its books and records hidden from Okada, who is a director of the company.

Okada is seeking to review the company’s financial records after becoming concerned about the use of certain funds invested through Aruze USA, a company he indirectly controls.

The complaint states that in 2002, in connection with the development of the Wynn Macau project, Steve Wynn first asked Okada for $30m, supposedly to finance due diligence, and then an additional $90m to fund other elements of the enterprise, for a total of $120m. Okada provided this funding through Aruze USA but claims that he has never seen any accounting for how this money was spent.

In May 2011, it states, Wynn Macau pledged to donate HK$1bn ($135m) to the University of Macau Development Foundation, which Okada objected to.

He is now requesting that the court steps in to allow him to access the company’s records.