27 CFR § 5.655.65
[Amendment] Prohibited practices
April 24, 2020
(a) * * *
(9) The words “double distilled” or “triple distilled” or any similar terms unless it is a truthful statement of fact. For purposes of this paragraph only, a distillation means a single run through a pot still or a single run through a column of a column (reflux) still. The number of distillations may be understated but may not be overstated.