Entry represents a fundamental threat to cartels. We study the extent and effect of this behavior in the largest price-fixing case in US history, which involves generic drug manufacturing. We link information on the cartel’s internal operations to regulatory filings and market data. There is a substantial increase in entry after cartel formation, but regulatory approvals delay most entrants by two to four years. We estimate a structural model and simulate counterfactual equilibria. Absent entry, cartel profits would be dramatically higher. Correspondingly, reducing regulatory delays by just 1–2 years equates to consumer compensating variation of $612 million–$1.5 billion.

We measure the breadth of insurance networks in the Massachusetts health insurance exchange. Using our measures, we estimate consumer willingness-to-pay for broad and narrow networks. We find that consumers have a wide range of plans available with dramatically different networks. While consumers value broader networks, their willingness-to-pay is smaller than the brand premium, indicating an additional role for brand preferences. Consumers place additional value on star hospitals, which may affect upstream negotiations. Finally, we find significant geographic heterogeneity in the value of broad networks.

We examine heuristic decision rules in consumer choice on health insurance exchanges using data from the Massachusetts Connector. Consumers may have difficulty making optimal choices in a complex environment. The heuristic “choose the cheapest plan” is suggested by the decision context, previous research, and the data: about 20% of enrollees choose the cheapest plan possible. We find evidence of this heuristic in many models, but while heuristics may play a role, preference heterogeneity is also important. Our most flexible models find an insignificant heuristic effect. In part because holding context fixed, this heuristic is observationally equivalent to extreme price sensitivity.