Although many of the procedural rules for auditing partnerships at the federal level have changed under the Bipartisan Budget Act of 2015 (the “BBA”), some principles—like the effect of actual notice—remain the same. Under the BBA, the IRS proposes partnership-level adjustments in a Notice of Proposed Partnership Adjustment (“NOPPA”) and later finalizes them in a Notice of Final Partnership Adjustment (“FPA”). If the IRS issues the FPA after the statute of limitations expires, the partnership can seek to invalidate it as untimely.
A reviewed Tax Court opinion filed March 9, 2026—Mammoth Cave Property, LLC v. Commissioner, No. 5401-24, 166 T.C. No. 4—shows the limits of “defective notice” arguments when the partnership actually received the NOPPA and participated in the process.