29 C.F.R. §§ 794.132–794.133

A sale by an enterprise engaged in the wholesale or bulk distribution of petroleum products will be included in the 25 percent limitation under the exemption only if it is made to a customer who engages in the distribution, in bulk and for resale, of “petroleum products”. The term “petroleum products” as used in section 7(b)(3) includes such products as gasoline, kerosene, diesel fuel, lubricating oils, fuel oils, greases, and liquified-petroleum gas. Sales to customers who are not engaged in the distribution of petroleum products will not be included in the 25 percent limitation.

“Bulk” distribution of petroleum products typically connotes those methods of distribution in which large quantities of the product are distributed in a single delivery or delivery trip. Thus, “bulk” distribution includes deliveries from bulk storage facilities at the establishment to the tank truck of a customer (whether or not at “wholesale”). It also includes deliveries made in series on a single trip on a delivery route to the storage tanks or facilities of a number of customers from a bulk supply of the product transported by tank truck, motor transport, or other motor carrier operated by the enterprise. Such deliveries are to be contrasted with such typical small-quantity individual deliveries as those made into the tank of a motor vehicle for use in its propulsion.