Whoa! What Just Happened With My Stock?

The Dow Jones Industrial Average (INDEX: ^DJI) jumped 1.4% on Friday, rising 173 points as retailers kicked off the official start of the holiday shopping season. But with global financial and economic concerns still an ever-present threat, no doubt the gains will be short-lived.

Yet while I expect the exuberance will be fleeting and we'll see greater volatility in the markets, some stocks even rose by double-digit percentages.

Yet resist the urge to high-five everyone in the cubicles next to you. Smart investors won't celebrate until they know why their stock surged, because without a fundamental basis for the bounce, these stocks could just as quickly make the return trip down.

No news is good news
"Truth is so rare that it is delightful to tell it," or so wrote Emily Dickinson. Obviously, the market hasn't taken my advice to avoid rare-earths mineral miner Molycorp, because it has been less than forthright with investors about SEC investigations into the accuracy of its public disclosures. While that's rarely something you want to buy into, Molycorp's stock has soared almost 40% since I penned that missive, as insiders including the company's CEO have bought tens of thousands of shares of the depressed stock.

Insider buying is often a bullish sentiment, but there are still lingering doubts about the company's financial wherewithal and the way the SEC investigation will play out. Although the market's ignored my advice, I think I'll be proved right in the end, so I'll rate Molycorp to underperform the markets on Motley Fool CAPS, the 180,000 member-driven investor community that translates informed opinion into stock ratings of one to five stars.

Tell me in the comments section below if you agree that Molycorp's outperformance is as rare as hen's teeth.

Rimshot!
Another company rubbing my nose in an underperform rating is Research In Motion, which has been rising based on hopes that its new BlackBerry 10 operating system will prove to be the lever that throws sales into high gear again.

Nokia (NYS: NOK) has garnered positive reviews for its new Lumia 920, suggesting that there is pent up-demand for a phone that will break the hegemony of Apple's (NAS: AAPL) iOS and Google's (NAS: GOOG) Android platform, and analysts suggest that carriers such as Verizon (NYS: VZ) and AT&T (NYS: T) want to break their stranglehold.

Yet theory and practice are two different things, and despite some hints that BB10 will be at least as good as iOS and Android, until it's in the marketplace we won't know -- and that's still a few months away. In the meantime, analysts are now simply trying to outdo one another with how upbeat they can sound about the tidal wave of change RIM will wreak on the market. One analyst calls for a price target of more than $40 a share, while another upped his estimates of phone sales to 35.5 million from 31.6 million ... all for something not even on the market yet!

This wall of euphoria seems ripe for tumbling down, so I'll be leaving my underperform rating on CAPS in place. It's currently losing to the indexes, as the stock has soared 55% since I weighed in on Research In Motion in August, compared with the S&P 500's 2% fall, but there seems too much riding on hope. Let me know below if you plan on upgrading your phone -- BlackBerry or otherwise -- to the new system in 2013.

Exercising discretion
Supplements maker Star Scientific continued the run higher it began more than one week ago, when it reported a financing deal that had the CEO and other large investors putting $20 million into the company through the exercise of warrants. The stock has moved higher by some 66%, as investors ignored the warning that the arrangement actually caused Star to leave a lot of money on the table in the process.

As it moves away from tobacco products and focuses on its Anabloc dietary supplement, perhaps they think this will still give the company sufficient capital to overcome short-term doubts about its viability and allow it to continue growing in the future. I'm not so certain about that, so after yet another day of running higher, I'll be rating Star Scientific to underperform the broad indexes on CAPS. Let me know, though, whether you think Star will smoke out the naysayers.

Whoa, Nelly!
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The article Whoa! What Just Happened With My Stock? originally appeared on Fool.com.

Rich Duprey owns shares of Apple. The Motley Fool owns shares of Apple and Google. Motley Fool newsletter services recommend Apple, Google, and AT&T. Try any of our Foolish newsletter services free for 30 days. We Fools don't 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.

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