- A provision in the tax law which allows a taxpayer to apply a net operating loss in one year to the three immediately preceding tax years, beginning with the earliest year. A net operating loss must be carried back unless the taxpayer elects to forego the carry-back and carry the loss forward. I.R.C. No. 172(b)Compare to carry-over
Black's law dictionary. HENRY CAMPBELL BLACK, M. A.. 1990.