What is the relationship between Steve Ballmer and Microsoft 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.

"As we move forward, we will continue to closely monitor the impact of the economic downturn on the company and if necessary, take further actions on our cost structure, including additional job eliminations," Microsoft chief executive Steve Ballmer said in an e-mail to employees on Tuesday.

Answer: owner_of