The only way I've ever known how to estimate this was by using the 'Short Interest' (% of Float) number provided by my brokerage house. This is part of the basic quote they show. Of course, this number is not reflected for SLGLF....that would be too convenient...assuming it is accurate.

If I had to evaluate the situation, I would guess that there are probably a small number of holders (mostly institutional), but their % of ownership is likely substantial. Just a guess based on the downward price pressure with neutral or even positive news.