This is purely speculative but could it be that a company (i.e. a future partner) is taking an anonymous position in Poet? A high profile company knows that when they take a position it will be at a much higher rate. In addition, their name alone will drive the price so by purchasing these available shares at much lower rates they are averaging down (so to speak). This very well could be foreign trades (i.e. European or US) as Mackwheaton described.

Any company wishing to take a position will not have to divulge their share position until they reach the 10% ownership level. So these purchases will help support the price as well as support options/warrant conversions along the way.

As mentioned, it is speculative but IMO a viable option.