This paper examines the impact of institutional investor’s investment horizons on corporate innovation. We conjecture that the presence of long-term institutional investors mitigates managerial myopia since long-term oriented institutions have more incentives to monitor with informational advantages, and that this will lead firms to engage in more innovative corporate activities. Using data on patents and citations of the U.S. firms over the period of 1980 -2003, we find that long-term institutional ownership is positively related to the number of patents, citations, and citations per patent. Our findings suggest that firms’ innovative activities increase with the greater presence of long-term institutional investors.