I suspect Dickens is a sable merle, but it's really hard to tell. He's the offspring of a pure-for-sable mother and a blue merle. Out of seven pups, none were listed as merled, which I find a bit strange; but if any of the pups were to be merles, he was the one. Not really a problem unless you mean to breed them, in which case, you need to take care that they're not bred to another merle.