Computer Problem Caused Price Errors on NASDAQ
buckthorn writes "An article running on Yahoo News states: 'A computer problem at an unidentified stock trader caused erroneous, exaggerated prices -- some as high as $950 per share -- to be posted to the Nasdaq Stock Market Friday morning for 1,680 different stocks, a spokeswoman for the Nasdaq said.'"
In the extended hours markets, some traders post bids or offers at outrageous prices, hoping someone will make a mistake. They will offer to buy some stock for $0.02 per share or sell some stock for 200.00 per share (that normally trades $20 a share) in hopes that someone screws up. The low cost of participating in an electronic market makes it easy to post these orders.
The real lesson is that stocks don't really have "a price" in a traditional sense. (At best, the price on the last transaction serves as a proxy, but is no guarantee of getting that price in the future). In reality, stocks have both a bid and an ask price. For thinly traded stocks (especially in the off-hours), the bid-ask spread can be very very large.
Buyer (and seller) beware.
Two wrongs don't make a right, but three lefts do.