What happened
Shares of hydrogen gas producer and fuel cell pioneer Plug Power (NASDAQ: PLUG) are among the biggest winners on the Nasdaq over the past year -- up more than 500%. The stock's had a rough couple of days, though, falling 5.5% on Friday and another 6.7% (through 12:15 p.m. EDT) today.
I think you can blame Citron Research for that.

Image source: Getty Images.
So what
Friday, if you recall, Citron put out a research report blasting Plug for having "never generated a profit" and being run by a CEO who "has sold 95%" of his own shares of the company.
Citron then proceeded to predict that Plug will miss its revenue targets this year (and not by a little -- by 40%) and said the stock, which sells for more than $12 today, is probably worth closer to $7 a share.
Now what
Plug stock sold off on Citron's report and, as there appears to be no new news on the wires that might affect the stock today, I can only conclude that investors who got spooked on Friday remain spooked today -- and for the same reason. Investors who have seen their stock quintuple in value over the past year are worried that the short-seller may be right and the stock is about to fall. They're selling to lock in their paper profits before that happens.
Lucky for Plug, there is something it can do to stop this sell-off: Deliver on its promises. Earn a profit, and prove the short-sellers wrong. Until Plug does that, though, the profitless stock will remain vulnerable to sell-offs like the one we're seeing today.
10 stocks we like better than Plug Power
When investing geniuses David and Tom Gardner have a stock tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.*
David and Tom just revealed what they believe are the ten best stocks for investors to buy right now... and Plug Power wasn't one of them! That's right -- they think these 10 stocks are even better buys.
*Stock Advisor returns as of August 1, 2020
Rich Smith has no position in any of the stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.
The views and opinions expressed herein are the views and opinions of the author and do not necessarily reflect those of Nasdaq, Inc.