This study investigates dishonest behavior among cocoa middlemen in Côte d'Ivoire, focusing on the role of observability and financial penalties in deterring such behavior. Using on a modified version of the "die-under-cup task", we examine the cheating behaviors of 151 cocoa middlemen over several interaction rounds. Our findings reveal that cheating is prevalent among cocoa middlemen, with 78% of players cheating at least once during the game. However, we found heterogeneous cheating patterns: 59% of cocoa middlemen consistently cheated when faced with a losing outcome, even when the risk of detection and sanction is high, 22% of them never cheated, and 19% did so occasionally. Key factors influencing cheating include age, religion, and risk attitudes. The study finds that introducing monitoring and sanctions significantly reduces cheating, highlighting the effectiveness of such mechanisms in deterring dishonest behaviors. By shedding light on the prevalence and determinants of cheating among cocoa middlemen, this study contributes to the experimental literature on dishonest behavior and understanding middlemen's role in agricultural value chains.