Many markets have a notion of the a volatility break. If the price moves too far in a short period of time, trading on the stock is suspended for a few minutes,

Many markets have a notion of the a volatility break. If the price moves too far in a short period of time, trading on the stock is suspended for a few minutes, while limit orders are collected. An auction crossing is then held to reopen the stock. This can happen several times in a row.