When you’re going about purchasing a human skull, it's always in your best interest to make sure it comes from a reputable source. Instinctively, you would want to know if the skull comes with any paperwork. But typically in the second-hand market, there is almost no paperwork that has survived. This is due to the fact that it wasn’t common practice to keep the papers that your skull came with. Think back to how often people keep the owner’s manual to a fridge they just purchased. In my three years of working with human osteology, and the hundreds of skulls that I’ve seen, I’ve only seen paperwork TWO TIMES!
Typically skulls are passed down from person to person, and they move around a lot. So the likelihood of the paperwork surviving is increasingly rare as it is moved place to place, and owner to owner. Also, companies weren’t known for marking any of their skulls except for the bone company Clay Adams. So please make sure when you purchase a skull you are getting it from a reputable source like JonsBones!