Pinned straw:
@Scoonie at one level it is hard to believe that ANYONE would short $CU6 in recent times at $2.
However, several weeks ago I heard a biotech analyst interviewed on a podcast (GS, I think) and he explained that a big thing in biotech fund management is to understand the newsflow cycle (i.e. clinical trials timelines).
Pre-revenue, big SP movements happen around FDA stage-gate milestones, and not much happens in between. And the "in between" periods can be 1-2 years. So it is apparently commonplace in biotech, to short stocks after milestone events (once price action has calmed), and then to buy back in advance of expected milestones (FDA milestone dates are fairly transparent, although there is risk around them in terms of timing - obviously as well as the outcome itself.)
Understanding this have given me a new lens to consider flows, shorting and pricing for biotech exposed to approval milestones.
(Sometimes, I surprise myself about just how little I really understand about how the capital markets work!)