16 CFR 424.2: Defenses.

No violation of § 424.1 shall be found if:

(a) The advertised products were ordered in adequate time for delivery in quantities sufficient to meet reasonably anticipated demand;

(b) The food retailer offers a “raincheck” for the advertised products;

(c) The food retailer offers at the advertised price or at a comparable price reduction a similar product that is at least comparable in value to the advertised product; or

(d) The food retailer offers other compensation at least equal to the advertised value.