South Korea's LIG Insurance Co. Ltd. has chosen American investment bank Goldman Sachs Group Inc. to advise on the sale of a controlling stake in the insurer, sources told Reuters on Thursday.

According to the report, the LIG stake plus a management premium could value the sale at around KRW500 billion to KRW600 billion ($475.62 million to $570.75 million). 

Korea Times in a report last month said that LIG's largest shareholder Koo Bon-sang and other shareholders will sell their combined 20.96% stake or 12.5 million shares in the non-life insurer. The stake is worth KRW381.6 billion as of the Wednesday close of LIG's share price, Reuters said. 

Koo and other members of LIG's owning family are exiting their stake to reimburse investors for losses sustained after buying debt issued by an affiliate construction company, the report said.

LIG Insurance has been the flagship unit of South Korean conglomerate LIG Group. It is the country's fourth largest non-life insurance company with capital assets estimated at KRW18 trillion, Korea Times said.