What happened

I guess you could call it "pin action." This morning, as you may have heard, investment bank JPMorgan announced it was upgrading shares of fuel cell company Bloom Energy (BE -0.97%) to "overweight."

Bloom stock responded rapidly to the upgrade (it's now up 6.3%), but rival Plug Power (PLUG -3.72%) is responding positively as well, rising 5.2% through 3 p.m. EDT.

Cartoon fuel cell car on palm of hand putting out H2 bubbles as exhaust.

Image source: Getty Images.

So what

And that kind of makes sense. After all, JP explained its upgrade of Bloom stock by referring to the shares' 21% decline in share price over the past month. Over that same time period, though, Plug stock declined nearly twice as much, falling 39%!

Granted, there are good reasons for Plug to be down right now: a big earnings miss that resulted in the company reporting negative revenues for the past year, for example; and a big earnings restatement. But even so, JP Morgan predicted that there are positive "catalysts" on the horizon which could help lift fuel cell stocks in the near future -- namely, "commercial introduction of hydrogen-based electrolyzers and fuel cell systems," reports TheFly.com.

Now what

With Plug stock down 39% over the past month, and nearly 60% off its highs as recently as January, investors appear to be betting that Plug stock is due for a rebound sooner rather than later -- and they may be right -- but they could also be wrong.

It's worth pointing out that with a market capitalization of more than $16 billion, and a valuation 11 times book value, Plug Power is hardly a cheap stock. And with a 12-month track record of producing negative revenues and a 24-year history of never earning a profit, success for this stock is still far from a sure thing.