26 U.S.C. § 1287: Denial of capital gain treatment for gains on certain obligations not in registered form

(a) In generalIf any registration-required obligation is not in registered form, any gain on the sale or other disposition of such obligation shall be treated as ordinary income (unless the issuance of such obligation was subject to tax under section 4701). (b) DefinitionsFor purposes of subsection (a)—(1) Registration-required obligationThe term “registration-required obligation” has the meaning given to such term by section 163(f)(2). (2) Registered formThe term “registered form” has the same meaning as when used in section 163(f).