On Friday, investors wrestled with nervousness about the rapidly changing situation in Russia and Ukraine, but the stock market eventually closed with small gains that sent the S&P 500 to all-time highs. Yet, many stocks failed to feel the bullish sentiment, as Alpha Natural Resources (NYSE: ANR), NewLink Genetics (NASDAQ:NLNK), and Furmanite (NYSE: FRM) all fell substantially in response to challenges affecting their particular businesses specifically.

Alpha Natural (ANR) closed down more than 12% following a scathing Goldman Sachs downgrade of the coal company. In issuing a sell rating, Goldman cited already-extensive cost-cutting efforts that leave Alpha Natural with little room to reduce expenses further, noting that high levels of debt and other liabilities will hamper the coal company's ability to restructure its operations to survive low coal prices. The analyst firm also believes that operating earnings in 2015 could be just half what most investors currently expect, citing weakness in the metallurgical coal market. Given the long struggles that the coal market has faced, the news hit not only Alpha, but also shares of other coal companies throughout the industry -- even ones that Goldman still has buy ratings on.

NewLink Genetics (NLNK) plunged 16% after the biotech company's update on its algenpantucel-L pancreatic-cancer drug study failed to deliver the upside surprise that investors had hoped to see. Although the company said that it had expected to continue the phase 3 trial at this stage, the doubling of NewLink's share price between early January and late February showed how much shareholders wanted to see such positive results from the drug that the company would end its trial early. For those who believe that the drug's potential remains strong, today's plunge could give them the buying opportunity they might otherwise never have gotten.

Furmanite (FRM) fell 9% as the technical-services company's quarterly results failed to impress investors. Even a 40% jump in year-over-year revenue and earnings per share that more than doubled fell far short of what investors had expected to see. Moreover, guidance for fiscal 2014 was no better, as Furmanite expects earnings-per-share growth of between 40% and 54%, falling below the 67% climb that analysts had projected. With investors having expected better returns from efforts by management to improve efficiency and boost margins, Furmanite will need to do a better job of delivering on the company's potential in order to satisfy shareholders in the future.

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