Private equity firm CVC Capital Partners is proposing taking Toshiba Corp private in a deal worth about $20 billion, a person familiar with the matter said, as the Japanese tech giant faces pressure from activist shareholders to improve its governance.

If realized, the deal will shield management of the scandal-hit conglomerate, particularly Chief Executive Nobuaki Kurumatani, from scrutiny amid calls from large overseas shareholders for greater transparency from its board.

“Toshiba received an initial proposal yesterday, and will ask for further clarification and give it careful consideration,” Toshiba said in a statement, without providing further details.

Kurumatani told a group of reporters earlier that Toshiba’s board would discuss the proposal on Wednesday, according to the Nikkei business daily.

Shares in Toshiba were untraded in early trade with buy orders overwhelming sell orders.

Kurumatani, a former banker at main Toshiba lender Sumitomo Mitsui Financial Group, headed the Japanese arm of CVC before joining Toshiba. One of Toshiba’s board members is a senior adviser at CVC Japan.

CVC is considering a 30% premium over Toshiba’s current share price in a tender offer, said the source, who declined to be identified as the matter is private. That would put the value of the deal at nearly 2.3 trillion yen ($21 billion) based on Tuesday’s closing share price of 3,830 yen.

The private equity firm declined to comment.

CVC is looking to expand in Japan, taking advantage of large Japanese companies under pressure to sell non-core assets and improve returns to shareholders. It is buying Shiseido Co’s lower-priced skincare and shampoo brands for $1.5 billion.

An acquisition of Toshiba, one of Japan’s few manufacturers of nuclear power reactors, needs government approval.

The battle between activist investors and Toshiba management is seen as a test case for whether the established giants of corporate Japan can respond to calls for better governance.