What happened
Hydrogen fuel cell stock Plug Power (PLUG 2.47%) had dropped 7.5% as of 10:35 a.m. EDT Monday after analysts at investment bank Morgan Stanley resumed coverage of the briefly dropped stock at a lower rating.
As StreetInsider.com reports today, MS now rates Plug Power stock not overweight (i.e., buy) as it used to, but only equal weight (i.e., hold).

Image source: Getty Images.
So what
Curiously, Morgan Stanley's price target on Plug stock is now $35 per share, about 17% above where the stock trades today, which you would think implies the analyst has more of a buy sentiment about it. And indeed, according to the analyst, "PLUG's product advantages, strong balance sheet, and strategic partnerships position the company well for the transition to a hydrogen economy."
The problem is that at Plug's current market capitalization of $17.6 billion, the analyst fears that "even after forecasting double-digit revenue growth and strong margin expansion," the company may have only "modest stock price upside."
Now what
Suffice it to say that this doesn't make a whole lot of sense. Either Plug Power stock is worth 17% more than it sells for today, or it has only "modest" upside -- it can't be both. And in fact, I'd argue it might not be either.
With trailing-12-month revenue of negative $100 million, and trailing losses of more than $560 million, I think there's a lot of uncertainty as to what Plug stock is really worth. I fear there's also a greater than zero chance that Plug Power stock bears significant downside risk to investors -- even after today's sell-off.