Employee vs. Employer Contributions
401(k)s like the Caterpillar Rail Division Retirement Savings Plan for Collectively Bargained Employees typically include both employee deferrals and employer matching contributions. While employee savings are always eligible for division, employer contributions usually depend on a vesting schedule. If the employee hasn’t met the required service time, part of the employer contributions may be non-vested and forfeited.
In many cases, only vested employer contributions can be divided. Your QDRO needs to specify whether it covers just vested amounts or if it attempts to assign future unvested funds as they vest (which the plan may reject).

