We no longer rely heavily on SSNs for identity verification. This is because a significant number of SSNs have been compromised (ex: The Equifax Hack) and individuals with new or thin SSN files are frequently unable to verify their identities with SSN. Read more here.
If your platform supplies SSN for users, there are two potential responses:
1) Successful, needs no further validation
The user's SSN did not match an SSN in our database and appears to be a valid SSN.
2) Invalid SSN information supplied
This SSN appears to be a match in our database or appears to be a false SSN.
If you get "Invalid SSN information supplied" frequently and believe there is a mistake, we're happy to investigate further. Just send the user ID/email/auth_key to email@example.com so we can take a closer look.