The phrase "rightful owner" refers to the person who has the legal or moral claim to something, typically because they are the original owner or have the proper authority over it. Full definition
If the domain is registered with their business name, some domain providers consider them as the actual rightful owner of the domain — which means if you ever need to switch web design firms, you'll be unable to do so without going through the firm. (platowebdesign.com)
How many more could be returned to rightful owners if we had such a mechanism in place to help reconnect them? (btoellner.typepad.com)
Working with local law enforcement, the program aims to track, detect, identify and return stolen property to rightful owners within the community. (thebronxchronicle.com)