OTC market switching and stock returns: some empirical evidence

In this study the effect on the common stock returns of 278 firms that switched OTC market segments from 1982 to 1987 is examined. It is hypothesized that abnormally positive returns are associated with news of the move from the NASDAQ to the NASDAQ National Market System (NMS) and that the market responds more favorably during pre‐NMS inclusion for stocks with low versus high liquidity before switching. Using event study methodology, results support these hypotheses. Unlike post‐listing studies, the evidence reveals no anomalous return behavior during the post‐NMS inclusion period studied.