Challenges to the reasonableness of pension plan actuarial assumptions are confronting corporate plan sponsors not only with regard to their own plans but also with respect to the calculation of withdrawal liability when they exit a multiemployer plan.

Since the enactment of the Multiemployer Pension Plan Amendments Act, withdrawal liability under the Employee Retirement Income Security Act has been derived by using actuarial assumptions and methods which “in the aggregate are reasonable” and “offer the actuary’s best estimate of anticipated experience under the plan.” In this regard, ERISA provides that the actuary “may rely on the most recent complete actuarial valuation used for [minimum funding] purposes.”

Read the full article, published by Law360 on Aug. 17, “Multiemployer Plans Poised For More Assumption Rate Suits.”