Yes, it's mostly related to the exercise of options but some of these options didn't expire till 2019. A couple expired in May of this year. There was another huge insider sale reported this afternoon and it didn't appear to be option related.
I would not be too concerned. Insiders are good at what they do but are not uniformly terrific investors. Moreover, they sell for many reasons unrelated to the future of the investment. At least that is my experience with board a members and other insiders.
"insiders are good at what they do but are not uniformly terrific investors"
While I do not entirely disagree with this statement, in the case of Mr. Herman, he is a terrific investor having an MBA at the University of Chicago and holding several board seats with several other companies. I know that Mr. Herman does not need the money nor was the reason option-expiration related, so this sale is certainly reason to dig a little deeper.
Most options exercised were 10 yrs old (from 2003) and expire in May. Prohl still holds almost 1/2 million shares and exercised only 86,601. The options expiring in 2019 were only controlling 8000 shares for Burgess (he has 0 shares left).