The TIN Matching program provides a numerical response indicator for each match request. The potential responses include:
‘0’ – Name/TIN combination matches IRS records
‘1’ – Missing TIN or TIN not 9-digit numeric
‘2’ – TIN not currently issued
‘3’ – Name/TIN combination does NOT match IRS records
‘4’ – Invalid request (i.e., contains alphas, special characters)
‘5’ – Duplicate request
‘6’ – (Matched on SSN), when the TIN type is (3), unknown, and a matching TIN and name control is found only on the NAP DM1 database.
‘7’ – (Matched on EIN), when the TIN type is (3), unknown, and a matching TIN and name control is found only on the EIN N/C database.
‘8’ – (Matched on SSN and EIN), when the TIN type is (3), unknown, and a matching TIN and name control is found on both the NAP DM1 and the EIN N/C databases.
For additional information see Publication 2108a, Online TIN Matching Program.