Division of Contributions
When dividing a 401(k) plan in a divorce, both employee and employer contributions are subject to division unless otherwise agreed. However, employer contributions may come with vesting schedules, which impact how much the employee actually owns at the time of divorce.
For example, if the employer contributes $10,000 but only 60% is vested at the time of separation, only $6,000 would be subject to division via QDRO. Your order needs to account for this nuance and clearly spell out what share the alternate payee receives of vested and potentially unvested amounts.

