29 C.F.R. § 779.204 : Labor — REGULATIONS RELATING TO LABOR — WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR — STATEMENTS OF GENERAL POLICY OR INTERPRETATION NOT DIRECTLY RELATED TO REGULATIONS — THE FAIR LABOR STANDARDS ACT AS APPLIED TO RETAILERS OF GOODS OR SERVICES — EMPLOYMENT TO WHICH THE ACT MAY APPLY; ENTERPRISE COVERAGE —ENTERPRISE; THE BUSINESS UNIT — Common types of ''enterprise.''

(a) The single establishment business. In the simplest type of organization-the entire business ordinarily is one enterprise. The entire business activity of the single owner-employer may be performed in one establishment, as in the typical independently owned and controlled retail store. In that case the establishment and the enterprise are one and the same. All of the activities of the store are "related" and are performed for a single business purpose and there is both unified operation and common control. The entire business is the unit for applying the statutory tests. If the coverage tests are met, all of the employees employed by the establishment are employed in the enterprise and will be entitled to the benefits of the Act unless otherwise exempt.
(b) The multiunit business. In many cases, as in the typical chain of retail stores, one company conducts its single business in a number of establishments. All of the activities ordinarily are related and performed for one business purpose, the single company which owns the chain also controls the entire business, and the entire business is a single enterprise. The dollar volume of the entire business from all of its establishments is added together to determine whether the requisite dollar volume tests are met. If the coverage tests are met, all of the employees employed in the business will be entitled to the benefits of the Act unless otherwise exempt.
(c) Complex business organizations. In complex retail and service organizations, questions may arise as to whether certain activities are a part of a particular enterprise. In some cases one employer may operate several separate enterprises; in others, several employers may conduct their business activities in such a manner that they are part of a single enterprise. The answer, in each case, as to whether or not the "enterprise" includes certain activities will depend upon whether the particular activities are "related" to the business purpose of such enterprise and whether they are performed with its other activities through "unified operation" or "common control," or whether, on the other hand, they are performed for a separate and distinct business purpose. As the Senate Report states,

related activities conducted by separate business entities will be considered a part of the same enterprise where they are joined either through unified operation or common control into a unified business system or economic unit to serve a common business purpose.

S. Rept. 145, 87th Cong., 1st Sess., p. 41; see also H. Rept. 1366, 89th Cong., 2d Sess., p. 9.) §§779.205 through 779.211 discuss the terms of the definition and may aid in making these determinations.

29 C.F.R. § 779.204