We revisit Maxwell's (1998) analysis to show that his results are incompatible with the assumption of full market coverage. As a consequence, the effects of MQS regulation on the high-quality firm's incentive to adopt a more efficient technology cannot be assessed in this model.

We model a vertically differentiated duopoly with quantity-setting firms as an extended game in which firms noncooperatively choose the timing of moves at the quality stage, to show that at the subgame, perfect equilibrium sequential play obtains, with the low-quality firm taking the leader’s...