Planned Obsolescence and Social Welfare*

Durable-goods marketing has an obsolescence effect on older models. I consider two cases: commitment (where the decision on how much to invest in marketing is made in the first period) and noncommitment (where the decision is made in the second period). I focus on the fact that the introduction of a higher quality model lowers the utility of consumers using an older model. I show that, in both cases, the equilibrium level of marketing rises above the socially optimal level. The point is that a larger obsolescence effect promotes replacement demand, driving the monopolist to spend more than is socially optimal.