Only a small % of the ~150M shares in the public float have traded since the FS was released. I imagine a number of investors could have sold based on the changing risk profile of CUU post-BFS. Many investors were expecting economics similar or better to the PFS that according to GS in November was above average for the 60 biggest copper projects on an IRR (13% IRR versus 8%) and cash cost basis (see chart below).

And even if the BFS met most investors' expectation, which it didn't, it is natural to have high turnover subsequent to completing a major catalyst.

The bigger issue is why is no one buying. And I think that has a large part to do with how the BFS changes the investment profile of CUU. A FS normally de-risks a project and provides an anchor to a company's valuation. SC's BFS is comparatively very weak (even compared to Galore Creek's at $2.60/lb Cu) and places all of CUU value in the more risky and still unproven upside drivers (e.g. inferred in-pit, district potential, cost reductions...). I still don't think CUU is worth $0.69 it is just harder to value properly post-BFS and will probably require a lot of investor turnover before it will be properly priced again.