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.

Immigrant activists have staged protests against Trump in Los Angeles and Washington, D.C. Companies including Comcast Corp's NBCUniversal and retailer Macy's Inc. have severed ties with him.

Answer: parent_organization: NBCUniversal, Comcast; owned_by: NBCUniversal, Comcast; subsidiary: Comcast, NBCUniversal; founded_by: NBCUniversal, Comcast