29 CFR 4043.30 - Liquidation.
(1) Is involved in any transaction to implement its complete liquidation (including liquidation into another controlled group member);
(2) Institutes or has instituted against it a proceeding to be dissolved or is dissolved, whichever occurs first; or
(3) Liquidates in a case under the Bankruptcy Code, or under any similar law.
(1)De minimis 10-percent segment. Notice under this section is waived if the person or persons that liquidate do not include any contributing sponsor of the plan and represent a de minimis 10-percent segment of the plan's controlled group for the most recent fiscal year(s) ending on or before the date the reportable event occurs.