Re: "I think you are confusing biobucks and the sort of dollars issued by the Federal Reserve. "
Not so fast. ZGEN has already received another $70M which was always very likely. And of course they have your biobucks (contigent milestones). And they still have kept 40% for themselves.
It is true they are still on the hook for 20% developement costs (including the first $100m), but I think the expected value of the deal is easily way over the $170M + you are talking of.
Imagine any model BMY could put together that would justify their side. Let's make up some numbers and see what we get.
P1 = probability of phase 2 success
P2 = probability of NDA accepted (assuming P1)
C = Total Dev cost after Zymos first $100M assuming P2 study passes
E = BMYs minimum expected risk adjusted earnings (not counting dev costs, milestones, etc) needed for the deal to break even.
V = deal value to ZGEN
V = 85+70+(P1*P2*360)+E*.67 - 100 - .2*P1*C
E = 85+70+(P1*P2*360)+.8*P1*C
(This discounts to 0 the extra milestones for sales and "other indications")
P1 = 40
P2 = 30
C = 600
E = 390
V = 311
P1 = 20
P2 = 20
C = 700
E = 338
V = 307
P1 =50
P2 = 30
C = 800
E = 529
V = 383
Notice the middle case (at a mere 4% chance of success) still value the deal at over 300M even using a model where BMY makes no profit. And you can't make the P's much lower, else the sales numbers would need to get absurd to generate the needed expected E.
SO, unless BMY has their head up their ass, the Lamda deal is worth well over $300M