Employee and Employer Contributions
Most 401(k) plans include both employee contributions (salary deferrals) and employer contributions (e.g., matching or profit-sharing). In divorce, only the portions contributed during the marriage are typically divided.
For example, if your marriage lasted from 2010 to 2020, the QDRO should direct the plan to calculate your interest in the contributions made during those specific years. This applies to both employee and employer-funded portions, but with a disclaimer about vesting (see below).

