Employee and Employer Contributions
401(k) plans typically allow both employee (deferral) contributions and employer (profit-sharing or matching) contributions. In most divorces, all vested balances are subject to division.
Employer contributions may be subject to a vesting schedule. For example, a participant might be 60% vested after three years. The QDRO can grant the alternate payee only the vested portion unless otherwise negotiated.

