26 USC 1287 - Denial of capital gain treatment for gains on certain obligations not in registered form
(a) In general
If 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).
If 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).