(a) "owner" shall mean any individual, partnership, trust or public or private corporation (including a cooperative housing corporation), holding the tenant's interest in a residential lease.

(b) "residential lease" shall mean a lease, sublease or other agreement that relates to all or a portion of a project, where all of such project, or the portion thereof to which such lease, sublease or other agreement relates, is designed and intended for the purpose of providing housing accommodations and such facilities as may be incidental thereto, the landlord's interest in which is held by the authority at the time such lease, sublease or other agreement is entered into.

(c) "underlying parcel" shall mean a parcel subject to a residential lease; provided, however, that in any case where the tenant's interest in a residential lease is held by a unit owner, "underlying parcel" shall mean the parcel in which the unit is included.

(d) the terms "unit owner" and "unit" shall have the meanings specified in section three hundred thirty-nine-e of the real property law. The term "parcel" shall have the meaning specified in section one hundred two of the real property tax law; provided, however, that in any case where the tenant's interest in a residential lease is held by a unit owner, "parcel" shall mean the real property deemed to be a parcel pursuant to paragraph (a) of subdivision two of section three hundred thirty-nine-y of the real property law. 2. (a) If an underlying parcel is exempt from real property taxes, or no real property taxes are payable with respect thereto, pursuant to the provisions of section nineteen hundred eighty-one of this title or of section twenty-two of chapter one hundred seventy-four of the laws of nineteen hundred sixty-eight, the residential lease for such underlying parcel shall provide for the payment by the owner of such residential lease to the authority of annual or other periodic amounts equal to the amount of real property taxes that otherwise would be paid or payable with respect to such underlying parcel, after giving effect to any real property tax abatements and exemptions, if any, which would be applicable thereto, if the provisions of section nineteen hundred eighty-one of this title or of section twenty-two of chapter one hundred seventy-four of the laws of nineteen hundred sixty-eight were not applicable to such underlying parcel.

(b) If an underlying parcel is owned by the city of New York, the residential lease for such underlying parcel shall provide for the payment by the owner of such residential lease to the city of New York of annual or other periodic amounts equal to the amount of real property taxes that are payable with respect to such underlying parcel, after giving effect to any real property tax abatements and exemptions, if any, which are applicable thereto.

(c) Where the owner of a residential lease is assessed for real property taxes with respect to the underlying parcel subject to such residential lease pursuant to section five hundred two of the real property tax law and section three hundred thirty-nine-y of the real property law, payment of such real property taxes shall be credited against the annual or periodic amounts of tax equivalency payments, payments in lieu of taxes or similar payments required to be paid under such residential lease.