October Term 2025 · Docket 23-1209
Can a pension actuary select assumptions after the measurement date?
M & K Employee Solutions argues that ERISA's timing rule fixes withdrawal liability as of the prior year's end. The IAM Pension Fund's trustees contend the statute allows actuaries to choose assumptions later.
Verified source milestones
- — An official oral-argument transcript was verified.
- — An official Court opinion was verified.
The arguments, in order
This case may have been argued more than once. Each entry below uses that session's official transcript. Later arguments do not erase earlier ones.
Argument 1 ·
What happened at the argument
Mr. Kenneally argued for the sides that brought the case. He said Section 1391 creates a clear timing rule. He emphasized the phrase as of as the key textual term.
Mr. Barber argued for the opposing sides. He said actuaries have selected assumptions after the measurement date for decades. He argued ERISA's provisions support that practice.
Mr. Roberts also argued for the sides that brought the case. He said the phrase as of is the key phrase in the case.
Read the official transcript for this argument · Official argument details
Sources used for this argument breakdown
- Official Supreme Court Transcript — file page 10, lines 33-7 — Transcript, file page 10, lines 33-7
- Official Supreme Court Transcript — file page 11, lines 39-9 — Transcript, file page 11, lines 39-9
- Official Supreme Court Transcript — file page 12, lines 29-31 — Transcript, file page 12, lines 29-31
- Official Supreme Court Transcript — file page 13, lines 41-45 — Transcript, file page 13, lines 41-45
- Official Supreme Court Transcript — file page 14, lines 23-41 — Transcript, file page 14, lines 23-41
- Official Supreme Court Transcript — file page 15, lines 35-17 — Transcript, file page 15, lines 35-17
- Official Supreme Court Transcript — file page 17, lines 13-27 — Transcript, file page 17, lines 13-27
- Official Supreme Court Transcript — file page 37, lines 51-17 — Transcript, file page 37, lines 51-17
- Official Supreme Court Transcript — file page 5, lines 11-23 — Transcript, file page 5, lines 11-23
- Official Supreme Court Transcript — file page 5, lines 25-9 — Transcript, file page 5, lines 25-9
- Official Supreme Court Transcript — file page 54, lines 35-35 — Transcript, file page 54, lines 35-35
- Official Supreme Court Transcript — file page 7, lines 11-15 — Transcript, file page 7, lines 11-15
- Official Supreme Court Transcript — file page 7, lines 33-37 — Transcript, file page 7, lines 33-37
- Official Supreme Court Transcript — file page 7, lines 47-53 — Transcript, file page 7, lines 47-53
- Official Supreme Court Transcript — file page 8, lines 23-45 — Transcript, file page 8, lines 23-45
- Official Supreme Court Transcript — file page 9, lines 37-49 — Transcript, file page 9, lines 37-49
A citizen's guide to the whole case
What this case is about
M & K Employee Solutions withdrew from the IAM Pension Fund. The plan calculated a large withdrawal liability. The company says the calculation used assumptions chosen after the measurement date. The Second Circuit agreed with the plan. The court in Metz was the first to bar that practice.
Official sources for this section
- Official Supreme Court Transcript — file page 37, lines 51-17 — Transcript, file page 37, lines 51-17
- Official Supreme Court Transcript — file page 5, lines 25-9 — Transcript, file page 5, lines 25-9
- Official Supreme Court Transcript — file page 54, lines 35-35 — Transcript, file page 54, lines 35-35
How the case got here
The Supreme Court heard oral argument in this case on January 20, 2026.
Official sources for this section
- Official Supreme Court Transcript — file page 5, lines 11-23 — Transcript, file page 5, lines 11-23
What each side wants
Mr. Barber argued actuaries have selected assumptions after the measurement date for decades. He said the Second Circuit in Metz was the first to prohibit that. He argued ERISA's provisions make clear the practice is allowed. The trustees want the lower court's ruling upheld.
Justice Kavanaugh asked how the sides that brought the case handle the terms reasonable and best estimate. He said those terms don't imply a specific timing rule. Justice Thomas asked whether the sides that brought the case knew about the valuation before withdrawing. Justice Gorsuch pressed on whether the actuary can use different information.
Official sources for this section
- Official Supreme Court Transcript — file page 37, lines 51-17 — Transcript, file page 37, lines 51-17
- Official Supreme Court Transcript — file page 5, lines 25-9 — Transcript, file page 5, lines 25-9
- Official Supreme Court Transcript — file page 54, lines 35-35 — Transcript, file page 54, lines 35-35
What each side says
Chief Justice Roberts raised a hypothetical about late-arriving information. He asked what happens if a company mails a correction after the measurement date. Mr. Roberts, the sides that brought the case' advocate, said the phrase as of is the key textual issue. The case turns on what that phrase means in context.
Justice Jackson noted the assumptions reflect the actuary's best judgment of future performance. She pushed back on the idea that the assumptions are something separate from that judgment. The justices probed whether the statutory language supports a rigid cutoff.
Official sources for this section
- Official Supreme Court Transcript — file page 37, lines 51-17 — Transcript, file page 37, lines 51-17
- Official Supreme Court Transcript — file page 5, lines 25-9 — Transcript, file page 5, lines 25-9
- Official Supreme Court Transcript — file page 54, lines 35-35 — Transcript, file page 54, lines 35-35
What the justices asked
Whether the phrase as of in Section 1391 requires the actuary to fix assumptions before the measurement date.
Whether the statutory terms reasonable and best estimate allow flexibility in selecting assumptions after the measurement date.
Official sources for this section
- Official Supreme Court Transcript — file page 10, lines 33-7 — Transcript, file page 10, lines 33-7
- Official Supreme Court Transcript — file page 11, lines 39-9 — Transcript, file page 11, lines 39-9
- Official Supreme Court Transcript — file page 12, lines 29-31 — Transcript, file page 12, lines 29-31
- Official Supreme Court Transcript — file page 13, lines 41-45 — Transcript, file page 13, lines 41-45
- Official Supreme Court Transcript — file page 14, lines 23-41 — Transcript, file page 14, lines 23-41
- Official Supreme Court Transcript — file page 15, lines 35-17 — Transcript, file page 15, lines 35-17
- Official Supreme Court Transcript — file page 17, lines 13-27 — Transcript, file page 17, lines 13-27
- Official Supreme Court Transcript — file page 7, lines 11-15 — Transcript, file page 7, lines 11-15
- Official Supreme Court Transcript — file page 7, lines 33-37 — Transcript, file page 7, lines 33-37
- Official Supreme Court Transcript — file page 7, lines 47-53 — Transcript, file page 7, lines 47-53
- Official Supreme Court Transcript — file page 8, lines 23-45 — Transcript, file page 8, lines 23-45
- Official Supreme Court Transcript — file page 9, lines 37-49 — Transcript, file page 9, lines 37-49
Why it matters
The ruling will determine when pension plan actuaries must lock in their assumptions for withdrawal liability calculations. It will affect how plans compute what withdrawing employers owe. The Second Circuit's Metz decision was the first to impose this timing restriction.
Official sources for this section
- Official Supreme Court Transcript — file page 37, lines 51-17 — Transcript, file page 37, lines 51-17
- Official Supreme Court Transcript — file page 5, lines 25-9 — Transcript, file page 5, lines 25-9
- Official Supreme Court Transcript — file page 54, lines 35-35 — Transcript, file page 54, lines 35-35
What happens next
This article currently covers the argument record. Use the official docket link for later case activity.
Official sources for this section
- Official Supreme Court Transcript — file page 10, lines 33-7 — Transcript, file page 10, lines 33-7
- Official Supreme Court Transcript — file page 11, lines 39-9 — Transcript, file page 11, lines 39-9
- Official Supreme Court Transcript — file page 12, lines 29-31 — Transcript, file page 12, lines 29-31
- Official Supreme Court Transcript — file page 13, lines 41-45 — Transcript, file page 13, lines 41-45
- Official Supreme Court Transcript — file page 14, lines 23-41 — Transcript, file page 14, lines 23-41
- Official Supreme Court Transcript — file page 15, lines 35-17 — Transcript, file page 15, lines 35-17
- Official Supreme Court Transcript — file page 17, lines 13-27 — Transcript, file page 17, lines 13-27
- Official Supreme Court Transcript — file page 5, lines 11-23 — Transcript, file page 5, lines 11-23
- Official Supreme Court Transcript — file page 7, lines 11-15 — Transcript, file page 7, lines 11-15
- Official Supreme Court Transcript — file page 7, lines 33-37 — Transcript, file page 7, lines 33-37
- Official Supreme Court Transcript — file page 7, lines 47-53 — Transcript, file page 7, lines 47-53
- Official Supreme Court Transcript — file page 8, lines 23-45 — Transcript, file page 8, lines 23-45
- Official Supreme Court Transcript — file page 9, lines 37-49 — Transcript, file page 9, lines 37-49
Official Court provenance
Official docket and case history · Official Supreme Court oral-argument detail page
Verified official opinions and orders
Title and summary sources
- Official Supreme Court Transcript — file page 37, lines 51-17 — Transcript, file page 37, lines 51-17
- Official Supreme Court Transcript — file page 5, lines 25-9 — Transcript, file page 5, lines 25-9
- Official Supreme Court Transcript — file page 54, lines 35-35 — Transcript, file page 54, lines 35-35
- Official Supreme Court Transcript — file page 37, lines 51-17 — Transcript, file page 37, lines 51-17
- Official Supreme Court Transcript — file page 5, lines 25-9 — Transcript, file page 5, lines 25-9
- Official Supreme Court Transcript — file page 54, lines 35-35 — Transcript, file page 54, lines 35-35
Revision history
- Revision 1 · Post Opinion ·
Correction: Rewritten to the concise citizen-facing editorial standard.
- Revision 2 · Post Opinion ·
Correction: Migrated to the dated official Court activity contract without model use.