He is a merle. Some breeders don't have any merle's in their breeding program as they have to be very carefully bred. You can't breed two merle's to each other, for example. some merle's are born deaf and blind. It is a color that is associated with some controversy. If he can see and hear and isn't going to be used in a breeding program, then there's no reason why you shouldn't have him for a pet.
"Having heard all of this, you may choose to look the other way.....
but you can never say again that you did not know." William Wilberforce 1759-1833