Short-sale Constraints and A-H Share Premiums Kalok Chan*, Hung Wan Kot and Zhishu Yang First draft: January 15, 2009 _______________ * Corresponding author. Chan is from Department of Finance, Hong Kong University of Science & Technology, Phone: (852) 2358 7681, E-mail:
[email protected]. Kot is from Department of Finance & Decision Sciences, Hong Kong Baptist University, Phone: (852) 3411 7558, E-mail:
[email protected]. Yang is from Department of Finance, Tsinghua University, Phone: (8610) 6277 1769, E-mail:
[email protected]. We thank Baolian Wang for his capable research assistance. We acknowledge the financial support from General Research Fund of Hong Kong Research Grants Council (Project Number 242408). All errors are ours. Short-sale Constraints and A-H Share Premiums Abstract We investigate the effect of different short-sale constraints of the H-share stocks on the A-H share premiums, based on H shares from Hong Kong and A shares from Mainland China. When the market goes down, we find that the prices of shortable H-shares decrease faster than those of non-shortable H- shares. As a consequence, the premium of A-H shares becomes larger for the shortable H-shares. We also find that lagged premium of shortable stock portfolio leads the premium of non-shortable stock portfolio, but not vice versa Keywords: Short-sale constraints, overvaluation, Hong Kong market, China A-share market Classification: G12, G15, G18 2 1. Introduction During the financial tsunami in the final quarter of 2008, there are controversies over the short selling activity around the global equity markets.