Cause-related marketing (CrM), defined as a firm’s communication activities designed to promote a consumer good or service by including an offer to contribute a specified amount to a designated nonprofit cause, has become a preponderant practice. In tandem with the development of CrM activities, criticism of CrM has increased; critics note that some CrM claims mislead consumers regarding their purchases’ donative impact. Critics such as consumers and nonprofit advocates are using ad parodies, noncommercial messages that mimic an actual advertisement. In this context, the study investigates how these ad parodies can result in a detrimental impact on consumers’ perceptual and behavioral evaluations of the sponsoring brand. By implementing a tightly controlled experiment comparing actual CrM campaigns and CrM parodies, the author shows that the detrimental effects of CrM parodies on brand attitude and word-of-mouth valence can be explained by greater skepticism toward the firm’s sincere and altruistic motivations. In addition, the author shows that a robust asymmetry emerges in which CrM ad parodies damage perceptual and behavioral evaluations of brands more than actual CrM campaigns improve them. The authors replicate the results for two kinds of critics and two types of brands. The results provide useful implications for theory and practice, documenting the backfire effect of poorly designed CrM, which may urge brands to move toward more self-regulation of CrM practices.