Employee vs. Employer Contributions
One complexity of this type of plan is distinguishing between what the employee contributed and what the employer contributed. In most 401(k) QDROs, both sources of funds are divisible—subject to the plan’s vesting rules.
Employer contributions may not be fully vested at the time of divorce. This means if the employee spouse later leaves the company before becoming fully vested, the alternate payee could end up with less than expected. Your QDRO should address this clearly—for example, by awarding a percentage of the vested account only.

