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Tax Research

Sources of IRS Materials

Abbreviation Name and Definition Government Source Westlaw Lexis
AOD Actions on Decisions
It is the policy of the IRS to announce at an early date whether it will follow the holdings in certain cases. An Action on Decision is the document making such an announcement. It is not intended to serve as public guidance and may not be cited as precedent.
Actions on Decisions (IRS website) IRS Actions on Decisions IRS Actions on Decisions
Acq. Acquiescence
The recommendation in every Action on Decision will be summarized as acquiescence, acquiescence in result only, or nonacquiescence. Both "acquiescence" and "acquiescence in result only" mean that the IRS accepts the holding of the court in a case and that the IRSwill follow it in disposing of cases with the same controlling facts. However, "acquiescence" indicates neither approval nor disapproval of the reasons assigned by the court for its conclusions; whereas, "acquiescence in result only" indicates disagreement or concern with some or all of those reasons.
Actions on Decisions (IRS website) IRS Cumulative Bulletin IRS Cumulative Bulletin and Internal Revenue Bulletin
C.B. Cumulative Bulletin
Hardbound compilation of the Internal Revenue Bulletins. Published every 6 months. 1919 to date.
Internal Revenue Bulletins (IRS website) IRS Cumulative Bulletin IRS Cumulative Bulletin and Internal Revenue Bulletin
C.C.A

Chief Counsel Advice
Written advice or instruction, under whatever name or designation, prepared by any national office component of the Office of Chief Counsel (OCC) which is issued to field or service center employees of the Service or regional or district employees of the Office of Chief Counsel and conveys any legal interpretation of a revenue provision, any IRS or OCC position or policy concerning a revenue provision or any legal interpretation of state, foreign or other federal law relating to the assessment or collection of any liability under a revenue provision.
Chief Counsel Notices
Used by IRS to notify personnel of policies, procedures, instructions, and delegations of authority. They do not constitute authority for avoiding the substantial understatement penalty.

Legal Advice Issued by Associate Chief Counsel (IRS website)

Chief Counsel (CC) Notices (IRS website)

IRS Chief Counsel Advisories and Notices

IRS Chief Counsel Advice

IRS Chief Counsel Notices

Deleg. Order
Del.Order

Delegation Order
Publication issued by the IRS where the Commissioner of Internal Revenue delegates a portion of his statutory authority. These appear in the weekly Internal Revenue Bulletin.
Delegation Orders and Policy Statements by Process (IRS website) IRS Delegation Orders IRS Cumulative Bulletin and Internal Revenue Bulletin
F.S.A. Field Service Advice 
Provide non-binding case-specific written advice issued by the National Office of Chief Counsel to field personnel of either the Internal Revenue Service or the Office of Chief Counsel to help them develop an issue or determine litigation hazards for both substantive and procedural matters.
*The IRS no longer issues Field Service Advice.
  IRS Field Service Advice IRS Field Service Advice Memorandums
GCM or Gen.
Couns.Mem.
General Counsel's Memoranda
Documents issued by the General Counsel's office to IRS staff that indicate the reasoning and authority used in revenue rulings, private letter rulings, and technical advice memoranda. IRS personnel use them in formulating positions.
* General Counsel Memoranda is rarely written anymore.
  IRS General Counsel Memoranda IRS General Counsel Memoranda
I.R.B. Internal Revenue Bulletin
Weekly IRS publication that contains the text of almost every primary non-judicial tax authority including: revenue rulings and procedures, regulations, Supreme Court tax decisions, treaties, tax legislation and reports, and acquiescences and nonacquiescences.
Internal Revenue Bulletin (IRS website) IRS Cumulative Bulletin IRS Cumulative Bulletin and Internal Revenue Bulletin
I.R.C. Internal Revenue Code
Federal tax law begins with the Internal Revenue Code (IRC), enacted by Congress in Title 26 of the United States Code (26 U.S.C.).
Tax Code, Regulations and Official Guidance (IRS website) Title 26. Internal Revenue Code Title 26 - Internal Revenue Code
I.R.M. Internal Revenue Manual
IRS operating policies and procedures.
Internal Revenue Manual (IRS website) Internal Revenue Manual Internal Revenue Manual
I.R.-News
Release
Internal Revenue News (Press) Releases News Release and Fact Sheet Archive (IRS website) Federal Taxation IRS News Releases  IRS News Releases

LTR
Ltr.Rul.

Letter Rulings
A general term that includes Private Letter Rulings, Determination letters and Technical Advice Memoranda issued by the IRS. See Private Letter Ruling for more information.
IRS Written Determinations (IRS website) IRS Private Letter Rulings  IRS Private Letter Rulings and Technical Advice Memoranda
Nonacq. Nonacquiescence
‚ÄčThe recommendation in every Action on Decision will be summarized as acquiescence, acquiescence in result only, or nonacquiescence. A nonacquiescence indicates that the IRS disagrees with the adverse decision in a case and will follow the decision only for the specific taxpayer whose case resulted in the adverse ruling.
Actions on Decisions (IRS website) IRS Cumulative Bulletin IRS Cumulative Bulletin and Internal Revenue Bulletin
PLR
Priv. Ltr. Rul.
Private Letter Rulings
Written determinations issued by the National Office of the Internal Revenue Service that interpret and apply tax law to a taxpayer's specific set of facts. PLRs deal with pre-return filing transactions and are issued directly to individual taxpayers at their request.
IRS Written Determinations (IRS website) IRS Private Letter Rulings  IRS Private Letter Rulings and Technical Advice Memoranda
Reg.
Treas.Reg.
Treasury Regulations
The official interpretation of the Internal Revenue Code by the IRS and the Treasury Department used to enforce internal revenue laws. There are proposed, temporary and final regulations.
Tax Code, Regulations and Official Guidance (IRS website) Tax Proposed & Adopted Regulations Proposed Regulations & Treasury Decisions
Rev. Proc. Revenue Procedures
Published statements of IRS practices and procedures. Revenue Procedures are published in the Internal Revenue Bulletin and the Cumulative Bulletin.
IRS Revenue Bulletins (IRS website) IRS Revenue Procedures  IRS Cumulative Bulletin and Internal Revenue Bulletin
Rev. Rul. Revenue Rulings
Written determinations released by the IRS that interpret the tax laws as applied to specific factual situations. Revenue Rulings are selected for publication in the Internal Revenue Bulletin because of their potential interest to the general public.
IRS Revenue Bulletins (IRS website) IRS Revenue Rulings  IRS Cumulative Bulletin and Internal Revenue Bulletin
SCA Service Center Advice
The Office of Chief Counsel provides legal advice to IRS Service Centers and related IRS functions with respect to their tax administration responsibilities. This advice is distributed and published to provide consistent legal advice to all affected IRS functions and Counsel offices on matters raised by the various functions.
  IRS Service Center Advice  IRS Service Center Advice
T.A.M.
Tech.Adv.Mem.
Technical Advice Memoranda
Memoranda prepared by the Internal Revenue Service in support of proposed Treasury decisions that provide background information and explain the reasoning underlying the proposals.
IRS Written Determinations (IRS website) IRS Technical Advice Memoranda IRS Private Letter Rulings and Technical Advice Memoranda
T.D. Treasury Decisions
Final and proposed regulations are issued as Treasury Decisions. Because the text of the regulation is added to the C.F.R., the most important information in the T.D. is the preamble. Treasury Decisions are published in the Internal Revenue Bulletin and Cumulative Bulletin.
Internal Revenue Bulletin (IRS website) Treasury Decisions  Proposed Regulations & Treasury Decisions
T.D.O. Treasury Department Orders
Documents issued by the Treasury Department as it exercises its control over the administrative organization of the IRS. These orders are selected for publication in the Internal Revenue Bulletin.
Internal Revenue Bulletin (IRS website) IRS Treasury Department Orders  
T.M. Technical Memorandum
Memoranda prepared by the Internal Revenue Service in support of proposed Treasury decisions that provide background information and explain the reasoning underlying the proposals.
IRS Written Determinations (IRS website) IRS Technical Memoranda   IRS Private Letter Rulings and Technical Advice Memoranda