The unique identifier in the Bidder Registration process is the nine-digit number assigned by the Internal Revenue Service (IRS) to business entities or individuals operating in the United States for the purpose of identification. It can be known by several different names including:
- Taxpayer Identification Number (TIN)
- Federal Identification Number (FIN)
- Federal Employer Identification Number (FEIN)
- Social Security Number (SSN)
- Employer Identification Number (EIN)
- Federal Tax Identification Number