Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of fuel-cell maker Plug Power Inc. (NASDAQ:PLUG) jumped another 15% today, touching a new 52-week high after being upgraded by an analyst.

So what: Cowen and Co. increased their price target on the stock to $5.50 from $5 and said the recent fuel-cell deal with Wal-Mart could be replicated with other large distributors. The analysts are expecting more such contracts and said the recurring revenue from such deals will be significant.  

Now what: Before going out and buying shares on this analyst note, keep in mind that shares closed yesterday above the $5.50 price target. The company's market cap currently stands at $686.4 million and revenue over the past 12 months was just $24.5 million. There's going to need to be a massive improvement in operations very quickly to justify that valuation, which will keep me out of the stock today.

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Travis Hoium has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.