1. Employee vs. Employer Contributions
In most 401(k) plans like this one, the employee’s contributions are always 100% vested. However, the employer match and other contributions may be subject to a vesting schedule. That means your spouse might not be entitled to the full balance if some of those employer-funded portions aren’t vested yet.
A proper QDRO should distinguish between the vested and non-vested balance at the date of division. Some plans—even within the same company—track multiple sources separately, and only a knowledgeable QDRO attorney will know how to demand the necessary data from the plan administrator.

