PCGS seems to get some of their information just by scraping the auction sites. For example, in this thread -- http://goccf.com/t/328661 -- PCGS CoinFacts had reported the sale price before I had the coin in my hand.
I've also started organizing most of my collection in PCGS Registry Sets. In that case, I'm effectively letting them know that I have these coins by certification number and whatever photos I upload, but I haven't told them how much I paid for most of them. Even if I did, I'm not sure my numbers would go into their sales/value records because I wouldn't necessarily be providing them with reliable information.
I've also started organizing most of my collection in PCGS Registry Sets. In that case, I'm effectively letting them know that I have these coins by certification number and whatever photos I upload, but I haven't told them how much I paid for most of them. Even if I did, I'm not sure my numbers would go into their sales/value records because I wouldn't necessarily be providing them with reliable information.



















