This is what I am wondering as well Tamaraw.
The insider buying could be for a number of reasons. e.g.
Stay ahead of the warrant sellers and keep the 10% plus insider relationship.
Or, gun for 20% ownership before the next AGM when the new Pinetree BOD comes on board. (And according to this, 20% ownership requires making a formal bid for the company. Maybe Pinetree wants to be part of a buyout syndicate? http://www.osler.com/NewsResources/Becoming-a-10-Percent-Shareholder-of-a-Canadian-Public-Company/
Or, just keep stoking the fire and keep the eyes on POET.