Derivatives

http://www.huffingtonpost.com/linda-r-monk-jd/did-al-qaeda-trigger-the_b_441825.html

The biggest spikes on American and United puts were on 9/6 and 9/7. They really don't belong in the category of 'sophisticated trades', either. They were the most basic of options.

It also makes little sense to interpret these options as something that al Qaeda would have purchased. Basic common sense tells you that huge spikes on airline puts would trigger alarms at every intelligence agency monitoring the markets. They should have ( emphasis on 'should have' ) triggered heightened security at all airports. If al Qaeda was trying to pull off a sneak attack, why would anyone in al Qaeda be foolish enough to send a loud telegraphed warning to the target by loading up on airline put options?