Duplicative aggregation.
(3) Duplicative aggregation. A plan may not be combined with two or more plans to form more than one single plan. Thus, for example, an employer that maintains plans A, B, and C may not aggregate plans A and B and plans A and C to form two single plans. However, the employer may apply the permissive aggregation rules of this paragraph (d) to form any one (and only one) of the following combinations: plan ABC, plans AB and C, plans AC and B, or plans A and BC.