A participant had been separated from his wife for 10 years (not a legal separation). Recently the wife and participant started divorce proceedings and a property settlement agreement was filed with the court in which the wife waived her right to benefits (50% QPSA) under the husband's money purchase & 401(k) plans. The settlement agreement does not meet ERISA requirements for a waiver of benefits (no notary, witness etc). The husband designated a beneficiary other than the spouse (no spousal consent) and died before the divorce was completed. Does anyone know of any cases or theories which may be helpful to the designated beneficiary in establishing the waiver of benefits in the settlement agreement as a waiver of the QPSA?

I can' cite any specific cases. But, if the agreement didn't meet the requirements of a qualifid domestic relations order or constitute a waiver of the QPSA, then the widow is entitled to the QPSA under the plan. Of course, you never know what a court will do given the right circumstances (such as a sympathetic plaintiff).

Perhaps one avenue is to determine whether, under state law, they were still considered married when they had been separated for 10 years. I don't know enough about domestic law to know whether this is possible in any state, and, maybe someone already determined that they are still legally married because they were in the process of getting a formal divorce.