Differentiated Durable Goods Monopoly: A Robust Coase Conjecture

The paper analyzes a durable goods monopoly problem in which multiple varieties can be sold. A robust Coase conjecture establishes that the market eventually clears, with profits exceeding static optimal market-clearing profits and converging to this lower bound in all stationary equilibria with instantaneous price revisions. Pricing need not be efficient, nor is it minimal (equal to the maximum of marginal cost and minimal value), and can lead to cross-subsidization. Conclusions nest both classical Coasian insights and modern Coasian failures. The option to scrap products does not affect results qualitatively, but delivers a novel motive for selling high cost products. (JEL C78, D42, L12)

A Coasian Solution to Problems of Initial Acquisitions

This article extends the Coase Conjecture to ethical issues of initial acquisitions of property rights. The Coase Conjecture complements the Lockean labour-mixing criterion to limit the boundaries of morally legitimate initial acquisitions of unowned property; whenever the Coase Conjecture applies, the Lockean Proviso that there be “enough and as good” left is automatically satisfied. This holds provided that, when a claim is made, the marginal willingness to pay for the last portion of it is zero (infra-marginally, willingness to pay may be arbitrarily high). Thus, the market price of the claim is zero, except for the part of it that the claimant inhabits or improves. “Excessive” claims therefore come to have a zero market price, so anyone may take possession of them, by purchase or theft. In either case they must compensate the original claimant by a zero amount. It follows that non-claimants do not lose by putatively “excessive” grabs by claimants. This article argues that any initial claims are just under these circumstances.