Efforts to fight international money laundering, corruption, and terrorist financing depend crucially on the prohibition barring the formation of anonymous shell companies. To study the effectiveness of this prohibition, we perform the first international relations (IR) field experiment on a global scale. With university institutional review board (IRB) clearance, we posed as consultants requesting confidential incorporation from 1,264 firms in 182 countries. Testing arguments drawn from IR theory, we probe the treatment effects of specifying (1) the international standards (managerialism), (2) penalties for noncompliance with these standards (rationalism), (3) the desire to follow norms through complying with international standards (constructivism), and (4) status as a U.S. customer. We find that firms prompted about possible legal penalties for violating standards (rationalism) were significantly less likely to respond to inquiries and less likely to comply with international law compared to the placebo condition. Some evidence also suggests that the constructivist condition caused significantly greater rates of noncompliance. The U.S. origin condition and the managerial condition had no significant effects on compliance rates. These results present anomalies for leading theories and underscore the importance of determining causal effects in IR research.