As a stockholder, I am happy with $90 per share especially having Pfizer backing the deal. The only ones that will make out on all the law suits floating around are the ambulance chasing lawyers.
According to prelim proxy, Pfizer bought exclusivity for another $3/share to bring final price to 90. One wonders if HSP could have fetched more if they had shopped around?
The official statement was that closing would be in second half of the year. That could mean anywhere from July 1 to Dec. 31. If it's 7/1, that's an annualized yield of almost 8% which is really good. Personally, I think it'll close around the middle of the year d/t the reasons you stated (probably 2 rounds of HSR). Looking at HSR, PFE and HSP are very different pharma companies. HSP only has one branded drug, and the rest are generic injectables, whereas PFE is traditional innovative pharma. So not a lot of overlap, but there will be some divestitures, but nothing that should delay the deal too much. PFE wants it done ASAP and they have good lawyers. The draft proxy statement should be interesting to read, and should be out in a few weeks. Overall, I think it's worth it too hang onto your shares as I think it'll close sooner than later.
Where did you get the info that merger will be completed in Dec? The only thing that I have read is some are estimating that the merger could be completed as soon as the end of the second quarter baring any problems with the FTC and any foreign intervention.