Despite the agency perspective of corporate tax avoidance, there is little empirical evidence that managers do extract rents derived from aggressive tax practices. This study investigates the association between tax aggressiveness and managerial rent extraction by focusing on informed insider trading, a self-serving action with an unambiguous impact on insiders’ personal wealth and representing the most direct channel through which managers expropriate outside shareholders. We find that insiders at firms more aggressive in tax avoidance gain significantly higher returns from insider purchases than insiders in less aggressive firms and this outperformance results from trading on future earnings news. We also find that insiders under the cover of aggressive tax practices more likely trade on bad news through insider sales and gain more from these trades. The overall evidence is consistent with aggressive tax planning serving managerial interests through gainfully exploiting private information and extracting rents from uninformed shareholders.