Rakuten Inc. Chairman and CEO Hiroshi Mikitani is named as a shareholder of a company in an offshore tax haven in recently leaked documents dubbed the Panama Papers, according to analysis of the documents by Kyodo News.

The data show that Mikitani was a stakeholder in a company established in the British Virgin Islands in 1995, before he started Rakuten.

According to the online retail site, Mikitani said he invested about ¥800,000, which later was returned to him only partially.

He said the investment was recommended by a foreign national he got to know either at a party or through a friend.

Rakuten quoted Mikitani as saying: "I don't recognize it as tax avoidance, and I have done nothing to be ashamed of."

The records give a Singapore address for Mikitani. The company's other shareholders are listed at the same address.

The leaked internal files from the Panama-based law firm Mossack Fonseca & Co. contain information about more than 200,000 offshore entities as well as about 370,000 individuals.

Kyodo has been conducting research on the papers in partnership with the International Consortium of Investigative Journalists.

The massive trove of files was first obtained by the German newspaper Sueddeutsche Zeitung and shared with the ICIJ, which classified the data by country and made a list. Media outlets that are in partnership with ICIJ have been analyzing their nations' data.

The ICIJ will release the full archive on its website on May 10 at 3 a.m. Japan time.