Civ. Code, § 1469

Each covenant made by the lessor in a lease of real property to do any act or acts on other real property which is owned by the lessor and is contiguous (except for intervening public streets, alleys or sidewalks) to the real property demised to the lessee shall, except as provided by Section 1466, be binding upon each successive owner, during his ownership, of any portion of such contiguous real property affected thereby where all of the following requirements are met:

(a) Such contiguous real property is particularly described in the lease;

(b) Such successive owners are in the lease expressed to be bound thereby for the benefit of the demised real property;

(c) Each such act relates to the use, repair, maintenance or improvement of, or payment of taxes and assessments on, such contiguous real property or some part thereof;

(d) The lease is recorded in the same manner as grants of real property, in the office of the recorder of each county in which such contiguous real property or some part thereof is situate. Such lease shall include the description of any such contiguous land described in any unrecorded instrument, the contents of which unrecorded instrument are incorporated by reference in such recorded lease.

Where several persons are subject to the burden of any such covenant, it shall be apportioned among them pursuant to Section 1467, except that where only a portion of such contiguous real property is so affected thereby, such apportionment shall be only among the several owners of such portion. This section shall apply to the mortgagee, trustee or beneficiary of a mortgage or deed of trust upon such contiguous real property or any part thereof while but only while he, in such capacity, is in possession thereof.