Insider Trading Subsequent to Initial Public Offerings: Evidence from Expirations of Lock-Up Provisions

Abstract

This paper explores the role of investment bankers and lock-up provisions in the market for new equity issues. In a sample of 1,948 IPOs, we find support for the notion that lock-ups serve as commitment mechanisms at the time of the IPO. Insiders of firms that are associated with greater informational asymmetries lock-up their shares for a longer period of time. We also find that underpricing is higher for firms that lock-up their shares for a longer period of time or lock-up a larger fraction of their shares. The average abnormal return at lock-up expiration is -1.2% and is larger for firms that lock-up a greater fraction of their shares and firms that are backed by venture capitalists. This price drop is inconsistent with rational expectations on the part of investors. Finally, we find that earnings forecasts made by both affiliated and unaffiliated analysts are more optimistic around lock-up expiration.