29 CFR §4043.35

1. (a)Reportable event. A reportable event occurs for a plan when any member of the plan's controlled group—
   1. (1)Commences or has commenced against it any insolvency proceeding (including, but not limited to, the appointment of a receiver) other than a bankruptcy case under the Bankruptcy Code;
   2. (2)Commences, or has commenced against it, a proceeding to effect a composition, extension, or settlement with creditors;
   3. (3)Executes a general assignment for the benefit of creditors; or
   4. (4)Undertakes to effect any other nonjudicial composition, extension, or settlement with substantially all its creditors.
2. (b)Waivers—(1) De minimis 10-percent segment. Notice under this section is waived if the person described in paragraph (a) of this section is not a contributing sponsor of the plan and represents 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.
   1. (2)Foreign entity. Notice under this section is waived if the person described in paragraph (a) of this section is a foreign entity other than a foreign parent.
   2. (3)Liquidation event. Notice under paragraph (a)(3) or (4) of this section is waived if reporting is also required under § 4043.30 and notice has been provided timely to PBGC for the same event under that section.