The United States patent system is unique in that it requires applicants to cite documents they know to be relevant to the examination of their patent applications. Lampe (2012) presents evidence that applicants strategically withhold 21%–33% of relevant citations from patent examiners, suggesting that many patents are fraudulently obtained. We challenge this view. We first show that Lampe's empirical design is inconsistent with both legal standards and standard operating procedures, including how courts identify strategic withholding. We then compile comprehensive data to reassess the empirical basis for Lampe's main claim. We find no evidence that applicants withhold citations.

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