Have you had the pup checked at a vet? Undestended testicles are not completely out of the ordinary. I'm not sure about the age range but it still may drop. Having him checked out by a good vet will give you an idea. If you bought the dog to breed and you have some type of guarantee then go back to the breeder to see if they will give you some money back. This really isn't the type of thing a breeder can foresee if you got the puppy very young. On the other hand if you just got the pup, then you would have noticed it when you were looking over the litter I would imagine. Either way it has no play on how healthy the pup will grow to be. He can be completely normal in all other ways. You could have him neutered if you aren't planning to breed and avoid any medical problems.
Snake Vom Eselspfad RN CGC (AKA Raina) 3/5/08
Pyrate CGC 4/1/03-5/16/12 RIP
Too many to list waiting at the bridge but remembering them all