Fiscalità e mercato azionario: Come interpretare lo stacco dei dividendi dei Titoli Italiani?

Abstract

To investigate the effect of taxation on stock price and trading volume around the ex-dividend day, we use the Italian Stock Market, where dividends on two classes of stock are taxed differently. When all investors face identical tax rates on dividends (holders of savings stocks), we find that the average price decline between the cum-and the ex-dividend day equals the after-tax valuation of dividends, and that there is no excess volume around the exday. When the tax rate on dividend income varies across investors (the common stock sample), we find significant escess volume around the ex-dividend day, as well as an average price decline smaller than the minimum after-tax valuation of dividends. The latter finding is inconsistent with the pure tax-trading hypothesis. It may be explained by the confounding registration effect: individual investors sell the stock prior to the ex-day to maintain their fiscal anonymity. However, a study of block trading activity, which is done by traders who are not subject to the registration effect, shows evidence consistent with the notion that a significant portion of the ex-dividend day trading is motivated by the differential valuation of dividends relative to capital gains. We also show that higher transaction costs result in higher ex-dividend day excess returns and lower abnormal volume. This finding is consistent with profit elimination activity by institutions and corporations.