Japanese to English Marketing Advertising / Public Relations Copyright law in advertising

I can find a definition of the term here (https://www.weblio.jp/content/コンテンツホルダー), but I can't figure out how you would describe English. Transliterating it as "content holder" seems to reek of 和製英語, and google searches for content holder in English don't really seem to come up with anything relevant either.

I can't give much context but basically it comes up on a slide explaining the main stakeholders in copyright law relating to the production of advertisements (it is one of the stakeholders). It is referring to a company performing a specific (contracted) role on behalf of an advertising agency. Aside from that, it's just a standalone word.

If anyone knows, or has any pointers for, a natural way of saying this in English it would be much appreciated.