(1)
In general, the payor of an account or instrument that is not a pre-1984 account nor a window transaction must use a TIN provided by the payee under penalties of perjury on information returns filed with the IRS to satisfy the due diligence requirement. Therefore, if a payor permits a payee to open an account without obtaining the payee's TIN under penalties of perjury and files an information return with the IRS with a missing or an incorrect TIN, the payor will be liable for the $50 penalty for the year with respect to which such information return is filed. However, in its administrative discretion, the IRS will not enforce the penalty with respect to a calendar year if the certified TIN is obtained after the account is opened and before December 31 of such year, provided that the payor exercises due diligence in processing such number, i.e., the payor uses the same care in processing the TIN provided by the payee that a reasonably prudent payor would use in the course of the payor's business in handling account information such as account numbers and balances.