Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
We show that merger activity and particularly waves are significantly driven by risk management considerations. Increases in cash flow uncertainty encourage firms to vertically integrate and this contributes to the start of merger waves. These effects are incremental to previously identified causes of wave activity. Our risk management hypothesis is further supported by cross-sectional differences in the likelihood that a firm vertically integrates, and by the post-acquisition characteristics of vertically integrating firms. These results are consistent with the view (from the industrial organization literature) that vertical integration is an operational hedging mechanism that reduces the cost of increased uncertainty.