A prior section 6658, act Aug. 16, 1954, ch. 736, 68A Stat. 826, authorized inclusion as part of the tax a 25 percent penalty in cases of violations or attempted violations of section 6851 of this title, prior to repeal by Puspan. L. 96–167, § 6(a), Dec. 29, 1979, 93 Stat. 1276.

Section effective Oct. 1, 1979, but not applicable to proceedings under Title 11, Bankruptcy, commenced before Oct. 1, 1979, see section 7(e) of Puspan. L. 96–589, set out as an Effective Date of 1980 Amendment note under section 108 of this title.