Given the input sentence, please extract the subject and object containing a certain relation in the sentence according to the following relation types, in the format of "relation1: word1, word2; relation2: word3, word4". Relations include: 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.

It has since split into Tribune Media Co, which owns broadcasting and digital media assets such as the WGN superstation, and Tribune Publishing Co, which owns newspapers such as the Chicago Tribune and Los Angeles Times.

Answer: owned_by: Chicago Tribune, Tribune Publishing; publisher: Chicago Tribune, Tribune Publishing; owned_by: Chicago Tribune, Tribune Media; headquarters_location: Tribune Publishing, Chicago; headquarters_location: Tribune Media, Chicago