(1) Associations taxable as corporations. — An association, trust or other unincorporated organization which is taxable as a corporation for federal income tax purposes.

(2) Exempt associations, trusts and organizations. — An association, trust or other unincorporated organization which by reason of its purpose or activities is exempt from tax on its income under the laws of the United States or this State.

(3) Real estate mortgage investment conduits. — An entity that is a real estate mortgage investment conduit (as defined in § 860D of the Internal Revenue Code of 1986 [26 U.S.C. § 860D], as amended).

(4) Designated and qualified settlement funds. — A trust that is a designated or qualified settlement fund (as defined in § 468B of the Internal Revenue Code of 1986 [26 U.S.C. § 468B], as amended, or Treas. Reg. § 1.468B-1 [26 C.F.R. § 1.468B-1]) shall be characterized as a trust for all purposes of this title and shall not be subject to tax under this chapter.

(5) Real estate investment trusts. — An entity that is a real estate investment trust, as defined in § 856 of the Internal Revenue Code of 1986 (26 U.S.C. § 856), as amended.

(6) Pass-through entities. — An association or other unincorporated organization that is a pass-through entity.