The marketing literature refers to the concept of brand capital and provides empirical evidence that firms with a large stock of well-established brands have an advantage in introducing new products. This paper develops a theory of brand extension as a mechanism for informational leverage in which a firm leverages off a good's reputation in one market to alleviate the problem of informational asymmetry encountered in other markets. It is shown that brand extension helps a multi-product monopolist introduce a new experience good with less price distortion. Thus, the paper provides a theoretical foundation for the concept of brand capital.

We develop a leverage theory of tying in markets with network effects. When a monopolist in one market cannot perfectly extract surplus from consumers, tying can be a mechanism through which unexploited consumer surplus is used as a demand-side leverage to create a “quasi-installed base” advantage in another market characterized by network effects. Our mechanism does not require any precommitment to tying; rather, tying emerges as a best response that lowers the quality of tied-market rivals. While tying can lead to exclusion of tied-market rivals, it can also expand use of the tying product, leading to ambiguous welfare effects.