Using a sample of 279 buyout backed firms, I examined the effect of lockup agreements on the firm’s stock returns. I found there to be a negative .8 percent cumulative abnormal return for the three-day period surrounding lockup expiration. Consistent with my hypothesis the CAR for the three-day period surrounding lockup expiration was less negative for buyout backed IPOs compared to venture capital backed IPOs. In addition, I found there to be an abnormal 24.24 percent increase in trading volume for the three days surrounding lockup expiration.

We examine 102 share lockup agreements following IPOs on the Swedish stock market and whether any abnormal returns exist in the days surrounding the expiration of lockup agreements. We also test three potential explanatory variables based on previous research, the length of the lockup agreement, the type of pre-IPO ownership for the firm (if it is backed by private equity or not), and if the lockup has multiple expiration dates (staggered lockup) or only one. Our results are unable to prove that there are abnormal returns surrounding the expiration lockups, and our variables fail to provide any explanation for the cumulative abnormal return (CAR). One variable that could prove interesting in future research is the change of free float, which we add in a robustness test and find a significant increase in explanatory power.