An Empirical Study of the Effect of Short Selling on the Bid Ask Spread

Soon selling was legally and uniformly reintroduced in Australia in 1986. This presented the opportunity to study the effects of permitting soon selling on stock market trading. The following study aims to determine the impact of short selling on the bid ask spread and thus transaction costs. The evidence presented in this paper supports the notion that soon selling acts to reduce the size of the bid ask spread. The public policy implication is that soon selling is desirable as it acts to reduce the size of transactions costs on the stock exchange.