California Code, Business and Professions Code - BPC § 17050

(a) In closing out in good faith the owner's stock or any part thereof for the purpose of discontinuing his trade in any such article or product and in the case of the sale of seasonal goods or to the bona fide sale of perishable goods to prevent loss to the vendor by spoilage or depreciation;  provided, notice is given to the public thereof.

(b) When the goods are damaged or deteriorated in quality, and notice is given to the public thereof.

(c) By an officer acting under the orders of any court.

(d) In an endeavor made in good faith to meet the legal prices of a competitor selling the same article or product, in the same locality or trade area and in the ordinary channels of trade.

(e) In an endeavor made in good faith by a manufacturer, selling an article or product of his own manufacture, in a transaction and sale to a wholesaler or retailer for resale to meet the legal prices of a competitor selling the same or a similar or comparable article or product, in the same locality or trade area and in the ordinary channels of trade.

The notice required to be given under this section shall not be sufficient unless the subject of such sales is kept separate from other stocks and clearly and legibly marked with the reason for such sales, and any advertisement of such goods must indicate the same facts and the number of items to be sold.