October 20, 2011
well, pharmaceuticals, for instance, could very well have increases when FDA approves something.
the idea is that when a stock price moves up or down, there is a pause.
FINRA proposes to reference the triggers by the primary markets that establish a Level 1 Market Decline of 7%, a Level 2 Market Decline of 13% and a Level 3 Market Decline of 20%.
if a stock comes off a halt, and brokers of the retail owners do not allow trading in the first several minutes, those traders who have near-instant access to the market get to set the price. this is often to the detriment of the stockholders. pausing for longer does not guarantee that any investor can buy the stock during that period of time. easily, stockholders' brokers' are colluding with the marketmakers, the shortsellers. if there is a halt, then it is important that all brokers be READY to trade when the stock opens for trading.
i am for a temporary halt so that the bid and the ask have time to populate. news can surprise a market and there might be a very quick reaction.
if indices depend on a particular stock's price, then the indices can be recalculated once the stock opens for trading again. the last price can be used to calculate an index until the halt or pause is concluded. i see no advantage to worry about repricing the index in light of a halt.
yes, if there is a pause or a halt, you can cancel all orders. notify brokers so that they can notify their customers and give their customers the opportunity to place their order with the same terms or change the terms.
it is ok to end a trading session for a stock if an extended pause conditions are triggered. no closing auction is necessary. it would particularly be offensive if the public could not trade and the rest of the market could trade.
all markets/exchanges should honor the trading pauses. all trading pauses should specify a time to resume. such information could be sent as a news item on common newswires.