26 U.S.C. § 6231 — Notice of proceedings and adjustment

(a) Notices. The Secretary^* must mail the partnership^* and partnership representative notice of (1) an administrative proceeding at partnership level about an adjustment to a partnership-related item^* or a partner’s distributive share, (2) a proposed adjustment from that proceeding, and (3) a final adjustment from it. A final notice is sufficient if mailed to the last known address of the representative or partnership, even after termination. The same first-sentence rule applies to a proceeding on a partnership administrative adjustment request under section 6227.
(b) Timing. (1) A proposed-adjustment notice may not be mailed later than the date set under section 6235 without considering its subsection (a)(2) and (3) rules. (2)(A) Unless the partnership waives this rule, a final notice may not be mailed before 270 days after the proposed notice. (B) Section 6235 supplies the limitations period.
(c) Repeat notices. If the Secretary sends a final notice for a year and the partnership petitions under section 6234, the Secretary may not send another final notice for that year unless fraud, malfeasance, or material-fact misrepresentation is shown.
(d) Rescission. With the partnership’s consent, the Secretary may rescind a mailed adjustment notice. A rescinded notice is not treated as an adjustment notice under this subchapter, and no section 6234 proceeding may be brought over it.