1. Division of Employee vs. Employer Contributions
A 401(k) account can include both employee contributions (which are always fully vested) and employer contributions, which may be subject to a vesting schedule. The QDRO must clearly define whether it covers only vested funds or includes a claim on future vesting amounts.
In many divorces, the alternate payee is granted a percentage of the “marital portion” of the plan. This often includes contributions made and earnings accrued during the marriage—whether vested or not. But defining this correctly takes experience. If the employee isn’t fully vested in employer contributions at the time of divorce, and the QDRO overreaches, it could be rejected by the plan administrator.

