Abstract We study the problem of synthesizing controllers that enforce hard state-constraints under occasionally missing state measurements. Although the problem can be solved as a partial information game via power set construction, it is undesired to do so because power set construction is computationally expensive. In this paper, we consider the instances where the missing data pattern can be specified by an automaton, and show that, for such cases, the synthesis problem admits a simpler solution. We introduce string automata and exploit the causality requirement to define the structure of the controller, and further use this structure to derive a product system. The synthesis problem then reduces to a full-information game on this product system. Two examples illustrate the efficacy of the proposed approach.