Completely understood with big pharma, because of the market cap. You won't see Johnson & Johnson go up 30,000 percent in one night LOL...but I just question that it's ever happened. I remember when Aquinox Pharmaceuticals did go from 1.84 to 55.75 intraday, which is a gain of what, like 3,000 percent? An investor on the board said he'd never seen anything like it in 40 years of investing. It ended up closing at around 10. If you go to Google finance, you can find the stock (AQXP) and look at the chart. You'll see the 52-week high of 55.75, but the chart won't register above 22 (it's closing price about 2 weeks later). It has since gone slightly below 10. That's probably the biggest gain I've ever seen on a stock in 1 day.