Yes, by attacking commonality (every company has risk warning section of hundred of items), he has shown his color and desperation.
Definitely it is a buy signal. If you want to win big, buy when most are not certain; if you want to be an average investors those who lose money to Wall Street crooks, then wait, wait and wail, perhaps after AF and his colonies have covered shorts and go long.
In agreeing your post, antiyaya, I want to share my personal story:
Late last year, when the company Nupathe (symbol Path) was attacked from various angles by shorts, its share price dropped; When the short attacked the company and predicted the company would be bankrupted in a couple of months even it had a FDA approval patch for use because the company had spent a whole year looking for partnership with no success, then lots of investors (retail investors and some funds) seemed really worry and sold their shares. I had followed that company for a while, I knew I was in a hard to come by situation of buying low, very low. So I started buying at $2, then the price dropped to $1.8, I hesitated for a couple of days, and eventually decided to buy more; then the price continually dropped to around $1.7, that's the time I had sold some of my positions, some profitable and some not profitable at the time of selling, I used all funds available to buy, accumulating shares much more than I initially anticipated.
Some sleepless nights, some nerve stretching days.
Then, one day when I woke up, a partnership deal was signed with Endo, the price increased significantly. People were happy and sell their shares. I was still holding and thought there might be better offer than Endo's.
Again, a better offer from Teva.
In my personal view, NWBO had much higher potential although more risk than Path. I am a buyer here (the Germans must not as dumb as AF, righ?)