We investigate the relationship between management ownership and market valuation of the fi rm, as measured by Tobin's Q. In a 1980 cross-section of 371 Fortune 500 fi rms, we fi nd evidence of a signifi cant nonmonotonic relationship. Tobin's Q fi rst increases, then declines, and fi nally rises slightly as ownership by the board of directors rises. For older fi rms, there is evidence that Q is lower when the fi rm is run by a member of the founding family than when it is run by an offi cer unrelated to the founder.
Management ownership; market valuation; board of directors; corporate governance; agency theory