(Bloomberg) -- Effissimo Capital Management Pte may make close to ¥100 billion ($768 million) from Toshiba Corp.’s buyout, with the value of the activist fund’s shares roughly doubling since it disclosed a stake in 2017.

Toshiba accepted a ¥4,620 a share offer Thursday from a Japanese consortium led by a domestic private equity fund, a move that may end a troubled chapter in the firm’s history.

Effissimo is the company’s largest stock holder with a 9.9% stake. Exactly how much it paid for the shares isn’t known, but the average cost is estimated to be about ¥2,330 a share, according to a Bloomberg News analysis of the fund’s shareholding disclosures. 

That suggests Effissimo will book a capital gain of ¥98.2 billion if it sells its shares into the tender offer expected to start in late July. 

A representative for Effissimo didn’t immediately respond to a request for comment.

The Singapore-based fund, set up by former colleagues of Japanese activist investor Yoshiaki Murakami, became Toshiba’s top shareholder in 2017 when Toshiba was reeling from a massive writedown on its nuclear power business.

The fund increased its stake in November that year when Toshiba raised ¥600 billion by selling new shares to about 60 funds.

Effissimo won a landmark shareholder vote in 2021 to appoint independent investigators to probe voting at the company’s annual general meeting. That led to a shocking report that detailed the government’s alleged backdoor dealings with the firm.

Read more: Secretive Hedge Fund Ends Long Silence to Take On Japan Icon

--With assistance from Yuki Furukawa and Go Onomitsu.

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