One concern about regulated monopolies entering unregulated vertically-related markets is that they will discriminate against competitors of their unregulated affiliates. However, prohibiting regulated monopolies from offering related goods may preclude production by the most efficient provider....

In this paper, I examine how firms' incentives to differentiate their products through the revelation of truthful information about product attributes varies with the distribution of consumer preferences for those attributes. I show that information will tend to be provided for large groups,...