Looks like Cortex is still on the Berlin exchange. One would think that Dr. Stoll may have tried to get the stock off that exchange. Other companies have apparently gotten themselves removed from there. The Berlin exchange is reportedly where naked shorting can be done more easily.
On the other hand, perhaps if a stock isn't traded there, then the PIPE financiers might be less eager to do financing deals with that company(?) In that case it would make sense for a small bio company to reluctantly stay on that exchange, in spite of the increased potential for manipulation.
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