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 OLED specialist Universal Display (Nasdaq: PANL) are seeing some heavy selling pressure today, down by as much as 13% in intraday trading after TheStreetSweeper.org ran a negative article on the company's recent deal with Samsung.

So what: TheStreetSweeper.org aims to uncover corporate fraud and misconduct, so featuring Universal Display on its homepage is bound to bring out the bears. The website has a disclosure policy -- similar to The Motley Fool's -- and interestingly the disclosure for that article indicates that TheStreetSweeper has established (through its members) a short position of 51,638 shares of the stock around $50 per share.

Now what: The report questions the terms of the deal with Samsung, and that the deal involves a license fee instead of ongoing royalty payments based on product sales. As the article boldly states, "In other words, that contract indicates, PANL may never capitalize on the popularity of Samsung smart phones featuring the Organic Light Emitting Diode (OLED) technology that has long been viewed as the key to its own future success." Universal Display is no stranger to volatility, and its long-term viability is far from clear. I like its role in the tech supply chain, but investors should tread carefully.

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