Using voluntarily disclosed data from 64 companies in the U.S., Cook
et al. (2004) examined the impact of open market share repurchases on
liquidity by focusing on actual repurchasing days. They find that share
repurchases help increase liquidity by narrowing bid-ask spreads and
lowering the price impact of order flows, especially in the NASDAQ
market. Likewise, Chung, Isakov, and Pérignon (2007) note that share
repurchases implemented by firms listed on the Swiss stock exchange
have a beneficial impact on liquidity. Their findings indicate that depths
and trading volume are higher and bid-ask spreads are smaller on
repurchasing days compared to non-repurchasing days. Other studies
done by De Cesari et al. (2011) and McNally and Smith (2011) also
provide clear evidence showing that bid-ask spreads are narrower on