With regard to your question which is the subject of this thread, the answer is no, at least not a Form 23C. The IRS an provide a Form 4340 (Certificate of Assessments, Payments, Other Specified Matters) -- or other similar documents -- in response to requests for "proof."
Here is what Revenue Ruling 2007-21 has to say:
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Frivolous tax returns; summary record of assessment. This ruling discusses and refutes the frivolous position taken by some taxpayers that before the IRS may collect overdue taxes, the IRS must provide taxpayers with a summary record of assessment made on a Form 23C, Assessment Certificate-Summary Record of Assessments, or on another particular form. These taxpayers claim that if a Form 23C is not provided, the assessment is invalid and the IRS may not collect any taxes due.
PURPOSE The Internal Revenue Service (Service) is aware that some taxpayers are claiming that, before the Service may collect overdue taxes, the Service must provide taxpayers with a summary record of assessment made on a Form 23C, ?Assessment Certificate-Summary Record of Assessments,? that is signed by an authorized employee or officer. If a Form 23C is not provided, these taxpayers claim that the assessment is invalid, and, consequently, that the Service may not collect any taxes due.
This revenue ruling emphasizes to taxpayers, promoters, and return preparers that, although an assessment is recorded on a summary record of assessment, such as the Form 23C or its computer-generated equivalent, the Revenue Accounting Control System (RACS) Report 006, there is no legal requirement that a summary record of assessment be provided to a taxpayer before the Service may proceed with collection activity. Further, if a taxpayer requests proof that an assessment was made, the Service is not required to provide any particular form or information in any particular format to the taxpayer so long as the Service provides the information required by Treasury Regulation §
301.6203-1 to the taxpayer. Any position to the contrary has no merit and is frivolous.
The Service is committed to identifying taxpayers who attempt to avoid their federal tax obligations by taking frivolous positions. The Service will take vigorous enforcement action against these taxpayers and against promoters and return preparers who assist taxpayers in taking these frivolous positions. Frivolous returns and other similar documents submitted to the Service are processed through the Service?s Frivolous Return Program. As part of this program, the Service determines whether taxpayers who have taken frivolous positions have filed all required tax returns, computes the correct amount of tax and interest due, and determines whether civil or criminal penalties should apply. The Service also determines whether civil or criminal penalties should apply to return preparers, promoters, and others who assist taxpayers in taking frivolous positions, and recommends whether an injunction should be sought to halt these activities. Other information about frivolous tax positions is available on the Service?s website at
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In short, the IRS considers demands for "proof of assessment" to be frivolous. Both the IRS and the courts can be quite hard on taxpayers who push frivolous arguments.
In support of the IRS position, the quoted Rev Rul cites the following tax cases: Goodman v. United States, 185 Fed. Appx. 725, 728 (10th Cir. 2006); Roberts, 329 F.3d at 1228; Carillo v. Commissioner, T.C. Memo. 2005-290; Michael v. Commissioner, T.C. Memo. 2003-26. In addition, an Appeals Officer is not required to obtain a Form 23C or other particular document in a collection due process hearing and may rely on a Form 4340 or MFTRA-X transcript to verify the validity of the assessment for purposes of section 6330(c)(1). See Nestor v. Commissioner, 118 T.C. 162 (2002); Perez v. Commissioner, T.C. Memo.
2002-274.