I guess it's to decrease identities theft in some way, but I do think you should be able to request a copy with your SSN on it if you need it. As demonstrated here, plenty of people use that document for other reasons than filing taxes. I think so few people actually mail in a copy of their W-2 with their tax returns anymore that it made sense but I think there should be a way around it if you need one. And it is optional, ADP went right in though.