What is the relationship between Global 500 and Fortune 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.

Over half of the companies on the newly-released 2015 Fortune Global 500 Index use the international publishing, research and consultancy firm Oxford Business Group (OBG) as a source of reference for their operations.

Answer: creator