Our client sponsors a DBP for employees under two different collective bargaining agreements. All requirements are met for treating each unit as a separate plan under 410(B).

In determining whether or not a partial termination has occurred, do you look at the entire participant population (both unions) or only the one union population that is experiencing the layoffs and ultimate closing? In other words, to determine a significant percentage, is the denominator the total participants, or the number in the affected portion, which is treated as a separate plan under 410(B)?

I believe that the answer is to look at the entire population of active participants. However, at the risk of dodging the original question, here are links to some earlier discussion on partial terminations.

http://benefitslink.com/boards/index.php?showtopic=7164