daytrading march 27 morning, page-39

Behind the massive trade that spooked the market

However, since this trade was deeply "in the money," the trader does not appear to be making a speculative options bet, but rather to be expressing a significant bearish view on the market as a whole. Indeed, this trade is effectively a $2.8 billion short bet on the S&P.

When a firm effectively shorts $2.8 billion worth of the S&P 500, people take notice and rush out of the way—no matter why that firm is actually doing it.

http://www.cnbc.com/id/101528314

A little more on this topic