It should be one or more institutions selling off big blocks at a big loss unless they bought in before 2009. It is pretty stupid to sell when you know the kind of growth this company will see in the next few years. The bottom is near IMHO.
Yes I am long with 150k shares and yes I have lost so far on this stock. But I am sure your days are numbered and the course will change soon. I urge you to close your short position and take your profit NOW.