Revenue Rulings
Revenue rulings are administrative decisions made by the IRS with respect to a specific taxpayer situation. Unlike other letter rulings like Private Letter Rulings, Revenue Rulings (or Rev Rules) do not relate to a specific individual and are binding on all taxpayers.
Revenue Procedures
Revenue Procedures (or Rev Procs) are official statements issued by the IRS as to how they will comply with sections of the Tax Code. Rev Procs are authoritative documents. Often, Rev Procs will deal with administrative or practical issues such as tax collection and administration.
Private Letter Rulings
Private Letter Rulings are rulings made by the IRS in response to a letter from a specific taxpayer. These rulings tell a taxpayer how the IRS will proceed in regards to a specific taxpayer issue or question. These rulings are binding ONLY on the taxpayer who solicited the question, not on taxpayers in general. However, PLRs can be used to anticipate how the IRS might treat a taxpayer in a similar situation.
Notices of Proposed Rulemaking
Notices of Proposed Rulemaking (NPRMs) are issued by the IRS to notify the public that a new proposed rule has been promulgated. The public is then allotted time in which to make comments on the proposed rule. The IRS must then respond to these comments and either defend the rule as is or make changes based on the comments. Proposed rules are not yet final rules and so are not binding.
Actions on Decisions
Actions on Decisions (or AODs) are memos issued by the Chief Counsel's Office when the IRS loses a case in one of the tax courts. These documents explain how the IRS will proceed on this issue in future litigation or explains whether or not the IRS will appeal the decision.
Technical Advice Memoranda
TAMs are memoranda issued by the IRS's National Office at the request of an IRS area director. The purpose of a TAM is to advise on positions that the IRS will take/has taken in order to maintain consistency in decisions and application of the law. TAMs are often requested when an IRS holding is unclear, usually because it is a complex, rare, or new situation.
