When you get the amount of volatility we've had recently, you will start to see all kinds of weird transactions, or as we used to say, when I worked at the Pacific Stock Exchange, 'bad prints'. Some exchanges are even canceling some trades that took place yesterday.
I remember once standing around at the post with other market makers, watching a stock that was trading at 35, 35 1/8, 35 1/4, 35 1/8, etc. (Remember, we used to trade in quarters and eighths back then.) All of a sudden, it showed a trade of 32, with no news coming across the wire. One of the market makers started yelling and selling and shorting all the limit buy orders. 'Sell, sell!'
All of the other market makers stood around staring at him with amusement. Some of them were even buying his short positions. Then all of a sudden, the stock traded back up at 35, 35 1/8, etc.
The market maker then started complaining, 'What the hell happened?' One of the guys working at the post told him that it was a bad print. The market maker asked what he could do about it, and the guy at the post said, 'I'll give you the phone number of the guy in New York who types in the trades, and you can work it out with him about his typo.' (Everything had to be manually typed in then. We didn't have the automation we have today.)
Needless to say, it made the day of the rest of the market makers.
Now in regards to the title of this article, this morning, Yahoo Finance showed Changyou.com Limited (CYOU) with a trading range of 28.98 to 100,000. I'm sure it was a bad print as Yahoo has updated their page, but you can see a screen shot of it below.
Don't forget to check out the stock that dropped from 41.78 to 4 cents yesterday.