SCOTUS Sides With Pension Fund in Withdrawal Liability Calculation Dispute

Why It Matters

The ruling gives plan trustees flexibility to incorporate the most current data, potentially increasing withdrawal costs for exiting employers and reshaping risk assessments for multi‑employer pension plans.

Key Takeaways

• Supreme Court allows post‑date actuarial assumptions if based on prior data
• Employers' withdrawal liability can swing dramatically with interest‑rate changes
• M&K faced a $4.36 million extra charge due to 6.5% rate
• ERISA requires “reasonable” assumptions, not a fixed adoption deadline
• Funds may still risk inflating liabilities despite the ruling

Pulse Analysis

Multi‑employer pension plans, which cover millions of unionized workers, have long grappled with how to value unfunded vested benefits when an employer leaves the scheme. Under ERISA, the liability is measured as of the plan year preceding withdrawal, but the actuarial assumptions used to calculate that liability—interest rates, mortality, and demographic trends—can dramatically affect the final number. The M&K Employee Solutions case highlighted this tension, as a shift from a 7.5% to a 6.5% discount rate inflated the withdrawal charge to over $3 billion, underscoring the financial stakes for both plan sponsors and trustees.

The Supreme Court’s decision, authored by Justice Ketanji Brown Jackson, pivots on the statute’s language that assumptions must be “reasonable” and reflect the actuary’s “best estimate.” By allowing assumptions adopted after the measurement date, the Court acknowledges that critical data often become available only later, but it also mandates that such data must pertain to conditions existing on the measurement date. This nuanced stance preserves the integrity of actuarial modeling while granting trustees the ability to incorporate the most accurate information, potentially raising withdrawal liabilities for departing employers.

For companies planning to exit a multi‑employer plan, the ruling signals a need for heightened diligence. While the measurement date remains the prior fiscal year’s end, firms must now anticipate that trustees may apply newer assumptions, which could increase costs. Legal counsel should review assumption methodologies and negotiate withdrawal terms that reflect realistic liability estimates. The decision may also spur legislative or regulatory clarification to balance employer protection with fund solvency, influencing future pension fund governance and market dynamics.