(a) The standard unique employer identifier of an employer of a particular employee is the EIN that appears on that employee's IRS Form W-2, Wage and Tax Statement, from the employer.
(b) A covered entity must use the standard unique employer identifier (EIN) of the appropriate employer in standard transactions that require an employer identifier to identify a person or entity as an employer, including where situationally required.
(c) Required and permitted uses for the Employer Identifier.
(1) The Employer Identifier must be used as stated in § 162.610(b).
(2) The Employer Identifier may be used for any other lawful purpose.
[67 FR 38020, May 31, 2002, as amended at 69 FR 3469, Jan. 23, 2004]