Guys you have this all wrong. Symphony wanted to unload 6 million shares. The reason for unloading the shares is immaterial. Now the block trade was done as follows. Symphony uses Barclays to act as a book runner I.e., they call around and find a buyer.,now maybe the buyer wanted only 5 million maybe 4 million but they took it all. The trade was done not on the open market but was an off market transfer. The buyer, however, it's clear began to immediately unload some shares. This was evident pre market and as soon as the market opened. Having taken 6 million at 4.86 she was looking to unload some risk. Now throw in the ISIS catastrophe and the mis- understanding and before you know it this is trading at 4.70 or almost a 3% discount to the block trade. DVAx regardless of cramer's pump is a screaming buy at 4.70. It will be 5 in a week and 6 before the FDa panel. You could see the bid size of 30 to 70,000 shares just looking to get filled. Now although a PR from the company would have allayed the cascade it's absence provided the opportunity.
Also, block trades of size are usually done at a discount to the market, at the end of it you would get more money for your shares this way versus selling 6M shares at the market. Symphony still holds 3M shares of DVAX, so they are confident but deleveraging risk.