A severance policy may be treated as an ERISA plan even if the policy is not in writing. ERISA governs only a severance plan that requires an "ongoing administrative program," requiring "complex administrative activities."Severance benefits that are part of an ongoing administrative program with clear eligibility standards or benefit provisions are subject to ERISA. Such oneoff severance agreements can constitute an ERISA plan under the right circumstances, even if the agreement doesn't mention ERISA. Severance Arrangement in Writing. A federal law, ERISA, requires that covered severance plans be in writing. 4. ERISA may apply to your separation arrangements. Her law firm focuses on ERISA disability, life insurance, severance, and pension benefit claims.