Much depends on the unknown. But let's do some rough math.
Teva suggests they will lose some $550 mil in sales in 2014 if they loses exclusivity. Say price is at 20% off, so taking Teva at its word, they expect generic to be ~$450 Mil for part year 2014 (May - Dec). Annualized? ~$770Mil/yr? (To me, that is worth far more than a mere $1-$2/sh on ~52mil shares.)
But I also expect Teva is light on their estimate. Such assume it is approved via the 505(j) pathway as a substitutable generic, and Sandoz/MNTA provide say only a 20% drop in price. Such might be high enough to gain the majority market share, but not trigger a price war w/ TEVA. Also expect TEVA to put in new price increases soon. So say within 4 month of a May launch, things stabilize w/ 60% Sandoz MNTA to 40% Teva with roughly the same size market for Rx. So it could be significantly bigger number.
But of course, MNTA has a partner, and instead of getting Net Sales w/ a large COPS, they will get a combination of milestones, royalty payments and other forms of consideration, much of what is still confidential.
Still, much of this misses the bigger picture. Sure, one could calc some $/sh for copaxone, but understand that with $MNTA we are at the start of a new business sector - US generic biologics. (OK - I know. The FDA calls this a quasi biologic. So don't get your panties in a twist. I think all can agree the FDA is clearly using this as a test case for what it might do with biologics.) W/ a generic form of Copaxone approved in the US, it also helps pave the reg path for MNTA's other programs as well. And as such, we are long $MNTA and expect to see the 20's plus soon.
Copaxone is a 4 billion dollar drug at current proprietary pricing and MNTA has around 52 million shares outstanding. Using a fairly conservative estimate of profits for MNTA for its generic sale I would guess $1-$2/share.annualized. Read the "Headlines" postings on Oct 28 and Sept 18 for some relevant quantitative analysis.