I have to wonder though, why would ES be an enticing breed for a puppymill?  Most of the dogs in pet stores tend to be small - poo mixes, maltese, poms, dachshunds.  If it's a large breed, it's likely a labradoodle, boxer, lab, golden - something common (or unique, like a dogue de bordeaux).  But most people don't even know what an English Shepherd is.  They aren't exotic or glamorous.  You'd think that would make them safely under the radar of the puppymiller.