I think there's an element of tax-loss selling also in the mix. But I believe the shorts were waiting, anticipating the tax-loss selling to bring the stock down faster and further. Probably the intention was to start bringing things down following the earnings call, which has seemed to be a pattern. However, the call seemed to be taken positively or neutrally at least, and had less selling pressure associated with it than with previous calls.
I suspect that the shorts - at least some of them - also trade the stock on the long end and helped to carry the stock back up to nearly $2 a few weeks ago and that gave them a more favorable reentry point, on the short side, early this month, or at least a decent exit point, on the long end.
The short interest went down slightly between mid-November and end of November -- but when we see the mid-December short interest I suspect we'll see that it rebounded to the level of mid-November and perhaps increased further.
The negative posts also approximately correlate, to the best of my recall, w/o researching the history of posts over recent weeks, with the recent ups and downs in the stock, all without any fundamental change in the outlook for the company, as far as I can see.
All in my opinion, of course.
Oh, and I'd like to add -- and I've said this before -- that I think the most honest posts/opinions about Sigma's prospects are those that are neither bleakly negative or glowingly positive about the company's odds of success. It's a speculative investment by its very nature, as a tiny emerging company. My opinion is that they have a decent shot, but I don't think anyone can say that their odds are tremendous and I certainly don't think that the naysayers can say that the company's odds are remote. Anyone can say anything, of course, so look for balance. I think they have a decent shot, and that's my opinion.