Section 2B. Except as otherwise provided in section three E, real estate owned in fee or otherwise or held in trust for the benefit of the United States, the commonwealth, or a county, city or town, or any instrumentality thereof, if used in connection with a business conducted for profit or leased or occupied for other than public purposes, shall for the privilege of such use, lease or occupancy, be valued, classified, assessed and taxed annually as of January first to the user, lessee or occupant in the same manner and to the same extent as if such user, lessee or occupant were the owner thereof in fee, whether or not there is any agreement by such user, lessee or occupant to pay taxes assessed under this section; provided, however, that whenever under the constitution and laws of the United States the privilege of such use, lease or occupancy of real estate owned by the United States cannot be taxed as aforesaid, but a leasehold or other interest in such real estate or the ownership of or an interest in buildings and other things erected thereon or affixed thereto, may be taxed, such interest or ownership shall be valued, classified, assessed and taxed to the holder thereof to the extent permitted by such constitution and laws. Except as otherwise provided, a payment purporting to be in lieu of a local tax for a particular year on real estate subject to this section shall be applied in reduction of the tax assessed under this section for such year with respect to such real estate. Notwithstanding any contrary provision of section twelve C, unless there is a different agreement, no tax assessed under this section shall be retained out of rent or recovered under section twelve C.

No tax assessed under this section shall be a lien upon the real estate with respect to which it is assessed; nor shall any such tax be enforced by any sale or taking of such real estate; but the interest of any lessee therein may be sold or taken by the collector of the town in which the real estate lies for the nonpayment of such tax in the manner provided by law for the sale or taking of real estate for nonpayment of annual taxes. Such collector shall have for the collection of taxes assessed under this section all other remedies provided by chapter sixty for the collection of annual taxes upon real estate.

This section shall not apply to a use, lease or occupancy which is reasonably necessary to the public purpose of a public airport, port facility, Massachusetts Turnpike, transit authority or park, which is available to the use of the general public or to easements, grants, licenses or rights of way of public utility companies; to the property of the United States, or any instrumentality thereof, for which payments are made in lieu of taxes in amounts equivalent to taxes which might otherwise be lawfully assessed, in behalf of the United States or any instrumentality thereof; or to the property of the United States, or any instrumentality thereof, which is used by a manufacturing corporation so classified under chapter fifty-eight.