Goldman Sachs Group Inc is working with Toshiba Corp on the beleaguered manufacturer's sale of part of its semiconductor business, people with knowledge of the matter said.

Toshiba is looking to sell 20 percent to 30 percent of the chip operation and will seek the first round of bids in early February, said the people, who asked not to be identified discussing the confidential sale process. Strategic investors and foreign private equity funds are among the potential bidders, and Toshiba aims to select a buyer by March 31, the people said.

Selling a stake in its profitable flash-memory arm would help Tokyo-based Toshiba cope with any losses stemming from its nuclear arm. Toshiba may write down the value of the nuclear business by an estimated 400 billion yen ($3.5 billion) to 700 billion yen, a person with knowledge of the company's finances said.

Canon Inc will consider an investment if invited, said Hirotomo Fujimori, a Tokyo-based spokesman. Spokesmen for Toshiba and Goldman declined to comment either on the potential sale or the estimated size of the write-down.