Tracy - that's the definitive answer I was looking for - thanks.

>The only difference is the placment and number of hyphens. Typically when an SSN or EIN is stored, a code identifying it as an SSN or EIN is stored as well. We must maintain SSNs and TINs because our parent company is a Premium Finance company and a major financial institution, and we have to conform to the U.S. Patriot Act of 2001 and the Sarbanes-Oxley Act of 2002 (specifically CIP - Cusomter Identification Program requirements). The information must be maintained for 5 years after the date the account is closed (or becomes dormant for CC)
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>>A client has a file of combined SSN and EINs - without the hyphens. Can one differentiate between SSN and EIN based on some 'prefix'? They are trying to diffrentiate between possible personal and business tax ids.