They aren't that secretive. They gave Supica & Nahas all the info to put in the Standard Cataolg of Smith&Wesson (the bible) and if you call them they will give you an answer on a serial number date. They don't have a published list of all their serial numbers and dates, but neither does Colt and many others. Ruger is about the only one I know of that has dates on their website.