Here are a few numbers. In January, across all trading systems, 1,541,777 shares of RVX traded hands.  Of these, Anonymous (001) traders bought 402,907 shares and sold 423,107 shares for net sales of 20,200 shares by these traders.  This means these traders represent roughly 25% of both buys and sells.  JMO but I'm not sure that much can be read into these numbers as within this group, on a net basis, they all could just be traders or one could be a big accumulator and many are sellers or one could be a big seller and many are accumulators or some other combination resulting in the net. I suspect that some of this activity is mm's balancing their book and short term trading, but that is just a guess.