34 C.F.R. § 12.13
(a) By eligible entities. A transferee or lessee may permit the use of all or a portion of the surplus Federal real property by another eligible entity as described in § 12.5, only upon those terms and conditions the Secretary determines appropriate if—
(b) By ineligible entities. A transferee or lessee may permit the use of a portion of the surplus Federal real property by an ineligible entity, one not described in § 12.5, only upon those terms and conditions the Secretary determines appropriate if—
(4) Any rental fees or other compensation for use are either remitted directly to the Secretary or are applied to purposes expressly approved in writing in advance by the Secretary.
(Authority: 40 U.S.C. 484(k)(4))