Today, health-care analysts David Williamson and Brenton Flynn look at one of the most popular and controversial stocks in health care, Dendreon. 

Favorable news about insurance coverage sent shares of the company about 10% higher today, but they eventually retreated a bit by market close. 

Investors are increasingly seeing insurers being a major driver of biotech stocks everywhere, with the decision to insure or not being a make-it-or-break-it moment for those companies. Today Dendreon got a big break, but this is hardly the sort of decision investors can bank on.

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This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.