Patent litigation reveals important information about the validity of the contested patent to other potential entrants. This paper explores the implications of such informational externalities for entry dynamics in the presence of multiple potential entrants. The nature of the entry game can be one of either waiting or pre-emption depending on the degree of patent protection. Therefore, the payoffs for the patentee and the initial imitator are discontinuous in the degree of patent protection. Furthermore, strengthening intellectual property rights is not necessarily desirable for the patentee. The analysis may also help explain the apparently puzzling practice of delaying patent suits.

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.

The literature on patent protection assumes a so called "fencepost" system, in which there would be no need to refer to the courts over questions of interpretation. In reality, we observe a myriad of patent infringement suit through which questions of utility, novelty, and nonobviousness are independently ruled on by a court. Therefore, patent litigation accompanying initial imitations can reveal important information about the validity of the contested patents for other potential entrants. This paper explores the implications of such information revelation through patent litigation. It is shown that the payoffs for the patentee and the initial imitator are highly discontinuous in the degree of patent protection. Furthermore, strengthening intellectual property rights is not necessarily desirable for the patentee. The analysis also has implications for interpreting empirical data on imitations lags.

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.