An economic experiment is used to investigate the presence and properties of injunctive norms regarding the division of a surplus between those who contributed to its creation. The experiment involves asking subjects what outcome should (as opposed to would) occur in a coordination game in which players’ strategies are the two distributional rules: (i) a rule based on dividing the surplus according to contribution to its creation or (ii) equal division of the surplus. We find that there is a difference in the injunctive norm's properties when the contributions underlying the coordination game are a result of effort as opposed to luck. When contributions are due to effort both the difference and sum of endowments influences the injunctive norm. This is not the case when contributions are determined by luck.