Disagree. Look back at trading volume in IDSA, if you bought on unusual volume days, chances are you lost money. 111,000 ahead of this news is pretty obvious that there was some hanky panky going on and if you know IDSA....you know what i'm talking about.
at the very least someone knew the announcement was coming... they had privileged information that was not available to the common shareholder and they were able to benefit illegally from this privileged information
for the rest of the shareholders to be expected to "guess" about big positive news because there just happened to be a big volume up day is not germane... you can't expect the common shareholders to divine that the news was extremely positive or that it pertained to positive earnings... it could have been any number of things that may have only been part of a one day wonder in the stock, such as an institutional buy
someone made a heck of a lot of money by buying in yesterday, and they did so on privileged information... who told who what is the only question
To be honest, I don't know exactly what the law says about insider trading. But in my limited experience, it seems that the SEC is much more likely to pursue cases where insiders dumped stock ahead of bad news than cases where they bought ahead of good news.