Unless otherwise indicated in the document, a power of attorney other than form 2848 will be presumed to grant the authority to receive notices or other written communication (or a copy thereof) required or permitted to be given to a taxpayer in any matter(s) before the Internal Revenue Service to which the power of attorney pertains.
The issuance of a CAF number does not indicate that a person is either recognized or authorized to practice before the Internal Revenue Service. Such determination is made under the provisions of Circular No. 230, 31 CFR part 10 . The purpose of the CAF number is to facilitate the processing of a power of attorney or a tax information authorization submitted by a recognized representative or an appointee. A recognized representative or an appointee should include the same CAF number on every power of attorney or tax information authorization filed. However, because the CAF number is not a substantive requirement (i.e., as listed in § 601.503(a) ), a tax information authorization or power of attorney which does not include such number will not be rejected based on the absence of a CAF number.
The fact that a power of attorney or tax information authorization cannot be recorded onto the CAF system is not determinative of the (current or future) validity of such document. (For example, documents which concern tax periods that end more than three years from the date of receipt by the IRS are not invalid for the period(s) not recorded onto the CAF system, but can be resubmitted at a later date.)
26 C.F.R. §601.506