Today is options expiration day. A lot of money can be made by the people who sold call options if Questcor is down today.
The only other news which could account for the selloff is the Republican vow to defund Obamacare. QCOR's drug is very expensive and if insurance doesn't cover it the average person can't afford it. Anything that raises uncertainty about health insurance has a disproportionate affect on QCOR.
I have no dog in this fight since I sold at $61 when QCOR violated it's technical support 50 day EMA.