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.

But if Telstra TV proves to be wildly popular, it could also be another nail in the coffin for Foxtel as customers opt out of more expensive Pay TV subscriptions to pick cheaper streaming services.

Answer: owned_by: Foxtel, Telstra; owner_of: Telstra, Foxtel