26 U.S.C. § 6324B: Special lien for additional estate tax attributable to farm, etc., valuation

In the case of any interest in qualified real property (within the meaning of section 2032A(b)), an amount equal to the adjusted tax difference attributable to such interest (within the meaning of section 2032A(c)(2)(B)) shall be a lien in favor of the United States on the property in which such interest exists. until the liability for tax under subsection (c) of section 2032A with respect to such interest has been satisfied or has become unenforceable by reason of lapse of time, or until it is established to the satisfaction of the Secretary that no further tax liability may arise under section 2032A(c) with respect to such interest. The rule set forth in paragraphs (1), (3), and (4) of section 6324A(d) shall apply with respect to the lien imposed by this section as if it were a lien imposed by section 6324A. For purposes of this section, the term “qualified real property” includes qualified replacement property (within the meaning of section 2032A(h)(3)(B)) and qualified exchange property (within the meaning of section 2032A(i)(3)). To the extent provided in regulations prescribed by the Secretary, the furnishing of security may be substituted for the lien imposed by this section.