But don't forget to check the Court of Federal Claims, since this refund court is available to taxpayers nationwide. When researching Tax Court and district court cases, check for cases that were appealed to your own circuit sincecases appealed to other circuits are not binding. Finally, the IRS might acquiesce to a Tax Court decision on which they lost. If they do acquiesce, this is a signal that the IRS doesn't intend to continue to fight on the issue decided in that case. However, a taxpayer may not rely on an acquiescence.
Final regulations are binding if they are current.
Note that proposed regulations are merely the Treasury's position, similar to a position espoused in a brief, and do not necessarily have the force of law. Temporary regulations generally go through notice and comment periods and have the same effect as final regulations. Legislative regulations have the force of law and are binding on the IRS and the courts. Interpretative regulations, on the other hand, are binding on the IRS, but not on a court. Revenue rulings and revenue procedures, which are IRS pronouncements of general applicability on substantive law and procedural law, will likely be binding against the IRS but not binding on the courts or taxpayers.