The Pottery Barn rule is an American expression alluding to a "you break it, you buy it" policy, by which a retail store holds a customer responsible for damage done to merchandise on display.
Pottery Barn is a United States-based upscale home furnishing store chain with retail stores in the United States, Canada, Puerto Rico, the Philippines, Mexico and Australia.
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It is an analogy often used in the political or military arena to suggest that if an actor inadvertently creates a problem, the actor is obliged to provide the resources necessary to correct it.
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In reality, Pottery Barn—a chain of upscale home furnishing stores in the United States—does not have a "you break it, you bought it" policy, but instead writes off broken merchandise as a loss, as do most large American retailers.
Legal doctrine also holds that a retailer incurs the risk that merchandise will be destroyed by placing it where customers can handle it and not doing anything to discourage them.