Yes, Suckerfish, PC selling does not make much sense.

As Mack wrote, PC is somehow a ghost. I also could find no track record, no success story. He worked for POET - which up to now is NOT a success story (yet). So why a hedgefund would hire him for a multi million salery? If he beleved in the POET story, he has the potential to grow to a multi-millionair (billionair?). Would he sell his shares for some more years in a hedge fund job? We should not forget that he said he was about to retire before he went to POET.

No, I see just two options:

1. He sold all shares as he did not see the bright future for POET and his investment.

2. He sold some to exercise his options - like GT. And still is one of the big shareholders.

I believe in 2, but who knows. Who sold all the rest of the shares (via 33)? Which house would be used e.g. by IBK? Possibly they were frustrated and hoped for fast return (after the tour through US, EU and Asia) and lost fate, trying to gain better profit with gold or oil?
All this is rumors. I am investing due to facts.