In this paper a model is developed from which the supply curve, of a stochastically produced good, can be estimated when the observations are constrained by a quota. It is shown that, for any (price, quantity) combination observed in the presence of a quota, we can simulate a corresponding (price, quantity) combination which could have been observed in the absence of a quota. This procedure is then employed to construct “free‐market” observations on Brazil's supply of sugar, with which the supply curve is then estimated, and production in the absence of sugar quotas inf