What is the relationship between Berkshire Hathaway and Warren Buffett in the context of the input sentence. Choose an answer from: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

With the $37.2 billion deal to buy Precision Castparts (NYSE: PCP - news ) announced Monday, US investment guru Warren Buffett is extending his storied Berkshire Hathaway (Sao Paolo: BERK34.SA - news ) holding company.

Answer: chief_executive_officer