26 U.S.C. § 1055: Redeemable ground rents

a redeemable ground rent shall be treated as being in the nature of a mortgage, and real property held subject to liabilities under a redeemable ground rent shall be treated as held subject to liabilities under a mortgage. Subsection (a) shall take effect on the day after the date of the enactment of this section and shall apply with respect to taxable years ending after such date of enactment. In determining the basis of real property held subject to liabilities under a redeemable ground rent, subsection (a) shall apply whether such real property was acquired before or after the enactment of this section. In the case of a redeemable ground rent reserved or created on or before the date of the enactment of this section in connection with a transfer of the right to hold real property subject to liabilities under such ground rent, the basis of such ground rent after such date in the hands of the person who reserved or created the ground rent shall be the amount taken into account in respect of such ground rent for Federal income tax purposes as consideration for the disposition of such real property. If no such amount was taken into account, such basis shall be determined as if this section had not been enacted. there is a lease of land which is assignable by the lessee without the consent of the lessor and which (together with periods for which the lease may be renewed at the option of the lessee) is for a term in excess of 15 years, the leaseholder has a present or future right to terminate, and to acquire the entire interest of the lessor in the land, by payment of a determined or determinable amount, which right exists by virtue of State or local law and not because of any private agreement or privately created condition, and the lessor’s interest in the land is primarily a security interest to protect the rental payments to which the lessor is entitled under the lease. For treatment of rentals under redeemable ground rents as interest, see section 163(c).