The past twenty years have witnessed the emergence of internet conglomerates fueled by acquisitions. We provide a simple theoretical model to shed some light on this. Following a large literature in management (Wernerfelt, 1984) we endow firms with a set of scarce competencies which drive their...

The model of perfect competition is one of the most famous, most important, and most misunderstood concepts in economics. Rather than aiming to be a full-blown model of real-world competitive markets, the perfect competition model isolates the decentralized coordination mechanism inherent in all...

In the last two decades, over 75% of U.S. industries have experienced an increase in concentration levels. We find that firms in industries with the largest increases in product market concentration have enjoyed higher profit margins and more profitable M&A deals. At the same time, we do not...