I have been following BIIB for a while and have a couple friends working in biotech industry. All of us, either investing in stocks or not, have been pretty much positive on the firm and were very suprised at the hugh slide after its earning release.
The company, Mass based, features its pretty edge-cutting R&D ability, product pipeline and partnership agreements with hospitals. Though Tecfidera got lowered expectation due to various reasons, the sales assumptions for ocrelizumab still has big prospects. I think the BIIB still have strong momentum and power in the long run.