Climbing 10.5% last week, Plug Power (PLUG -7.00%) stock showed some pep in the middle of July. This week, however, the hydrogen and fuel cell stock isn't extending the gain. Although the company didn't have any news to report that would substantiate the decline, investors have, nonetheless, chosen to distance themselves from Plug stock.

According to data provided by S&P Global Market Intelligence, Plug Power stock has dropped 18.5% from the end of last Friday's trading session through the market's close on Thursday.

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Image source: Getty Images.

Putting Plug's plunge in perspective

There are a couple of reasons behind the drop in Plug stock this week. For one, Plug stock has had a pretty rough go of it in 2025. Through the first six months of 2025, shares had dropped 30%. With investors clicking the buy button last week due to a bullish report on the fuel cell industry's prospects, investors may have felt that this week is a good time to cut their losses -- or even collect some profits -- from the otherwise beleaguered stock.

Another source of discomfort for Plug investors this week could stem from a peer. Bloom Energy (BE -2.22%) reported a notable deal with Oracle to deploy fuel cells in support of powering data centers. The same can't be said for Plug Power, so investors looking for fuel cell exposure may be jumping ship with Plug in favor of Bloom Energy.

Does the recent drop in Plug stock provide a buying opportunity?

While Plug stock is a little less expensive now, it doesn't mask the fact that there are ample concerns regarding the company's financials. Therefore, investors should look elsewhere for a hydrogen investment.