The policy would have to be read in conjunction with your state law.  But if the policy holder designated you 50% and the other 50% beneficiary is unclear then I would think that one very good possibility is that the unclear beneficiaries portion reverts to the decedent's estate and is distributed according to the Will or the state intestacy statute. If a party steps forward and claims it then the insurance company will probably start an interpleader action.  Your half seems safe.  Good luck.