Good question, Cottonmouth.

I referred to this set of warrants because someone suggested that if Hepa wanted to support RVX it could excerise these warrants (at the strike price of 3.21 when the stock is under a dollar!!).  I tried to point out that it didn't make sense for Hepa or anyone else holding these warrants to exercise them unless the stock price was much higher (RVXOT did a better job of explaining the situation in a subsequent post).  These are non-tradeable warrants.  The tradeable warrants also expire this year, I believe, and could also be extended so that they might be exercised if the share price improves.  There is nothing to be done for expired warrants (and, like you, I have held plenty of those).  That is the risk of warrants and I accept it. 

However, some companies do extend warrants when there is good reason to believe that the share price will rise in a reasonable time frame (I consider this to be no longer than a year after expiry).  This is a bit of reward to at least some shareholders but is at sole discretion of the company.  In this case, it might also be a good deal for the company because in any negotiation of new issues of shares and warrants, Hepa might not agree to a strike price of 3.21 in a short time frame (given the recent performance of RVX).  All just food for thought and certainly more realistic than expecting Hepa to pay 3.21 for shares at the current stock price.

Jupe