The author uses a panel of startup activity for the U.S. states for the period 1977 to 2013. He exploits Michigan’s inadvertent policy reversal in 1985 that transformed the state from a non-enforcing to an enforcing state as a quasi-natural experiment to estimate the causal effect of enforcement on startup activity. His findings offer little support for the widely held view that enforcement of non-compete agreements negatively affects the entry rate of new firms or the rate of jobs created by new firms. In a difference-in-difference analysis, the author finds that a 10 percent increase in enforcement led to an increase of about 1 percent to about 3 percent in the startup job creation rate in Michigan and, in general, to essentially no change in the startup entry rate. Extending his analysis to consider the effect of increased enforcement on patent activity, the author finds that enforcement had differential effects across technological classifications. Importantly, increased enforcement had a positive and significant effect on the number of quality-adjusted mechanical patents in Michigan, the most important patenting classification in that state.