I'll bite. There's been a dilution with a sale of $30 million worth of new shares at $2.84 a piece to a private investor which I think is positive; this stock also has the overhang of warrants owned by its biggest investor expiring in December Platinum-Montaur. They don't want to own more than 10% for administrative reasons presumably and they have to sell of existing shares to make room for the new ones coming in or get NAVB to accommodate them some how. Selling now could be a reaction to this inevitable sell off.
I do think the underlying story is sound. Hbomb has said that he doesn't believe its current market cap of $300 million is justified from the approved indications of Lymphoseek in breast cancer and melanoma after turning over half of revenues to its partner Cardinal Health, however, I think there are looming approvals for much more general indications for sentinel lymph node mapping the US and Europe which could widen the scope of Lymphoseek by quite a bit. I think the recent good data from head and neck cancer would justify this as those are areas specifically rich with lymph nodes. The product is superior in its function, less painful, less expensive, and more profitable to clinics with its pass through code.
Don't forget its deep pipeline of other products, such as an alzheimer's diagnostic agent which matches the best in class product and has better logistical properties because of its longer half life, a parkinson's diagnostic agent, and RIGScan which will be humanized and in trial next year. The potential here is huge but should be appropriately discounted due to risk; Medicare decided to only partially reimburse Amyvid, but Eli Lilly is fighting this. Lymphoseek alone should justify this market cap and the pipeline looks very promising.