jimmy, if you have a product that saves a company's annual $8B market share and its 80%+ gross margins, you don't trade that access for 2 or 3 cents on the dollar. You charge "primo" for it (and it might explain why there is no deal, yet, as Dr. M is no fool around an M&A table).
If Biogen believes 2-73 may save its MS drug market, then 10% for $400-600 Million with a royalty of 12-15% is reasonable and, possibly a carrot, to offer Biogen, right of first refusal to use it in other therapies.
2-73 will not be given away cheaply!