Русско-англо-русский юридический словарь

In this Schedule “rightholder” in relation to a relevant work means — (a)an owner of the copyright in the work, [...] (Copyright, Designs and Patents Act 1988)

Right-holder. A term used to indicate anyone with a proprietary interest in a copyright or other intellectual property right: for example, an owner or (sometimes) exclusive licensee. (Canadian Online Legal Dictionary)

A right holder refers to a legal entity or person with exclusive rights to a protected copyright, trademark or patent, and the related rights of producers, performers, producers and broadcasters. A right holder may license a portion or all of a protected work through international legal and licensing provisions. (techopedia)