1. Employee vs. Employer Contributions
When dividing a 401(k) plan, the first step is to determine which contributions should be included. Employee contributions, made through salary deferrals, are typically 100% owned by the participant. Employer contributions, however, may be subject to a vesting schedule.
If the participant spouse isn’t 100% vested in employer contributions, the nonparticipant spouse may not receive a portion of those funds. The QDRO should clearly identify which contributions are being divided and whether unvested portions are excluded or addressed in some other way.

