As a spouse you already own a one half interest in his 401(k) contributions during the marriage. Your share could be distributed out to you right now in a divorce proceeding to a rollover IRA without penalty or tax under a Qualified Domestic Relations [court] Order (QDRO). Property in a marital dissolution in Washington is not necessarily divided 50-50, so you could argue for a greater than 50% share based on your payment of the medical insurance costs.