Resist the urge to high-five everyone in the cubicles next to you. Your stock may have just strapped on a rocket pack and taken off for the moon, but smart investors won't celebrate until they know that upward leap was justified. Without a fundamental basis for the bounce, these stocks can quickly make the return trip down.

Is now the time to lock in profits, or is this just the first step toward even higher valuations down the road? Let's examine several stocks that just hit the afterburners, and see whether they're truly headed into orbit.


CAPS Rating (out of 5)

Wednesday's Change

Orexigen Therapeutics (Nasdaq: OREX)



Lucas Energy (NYSE: LEI)



VirnetX Holding (NYSE: VHC)



One day after stocks soared 128 points, the market turned around yesterday and fell more than twice that amount, 280 points or 2.2%, as economic data confirmed what people already knew: the economy remains in a dire condition. So stocks that went significantly higher are pretty big deals.

The short story
Hope springs eternal, and when investors have been as beaten and bludgeoned as Orexigen Therapeutics' investors have, any bit of straw-grasping can trigger volatile trading session. The obesity-drug developer did little more than announce that it will have an announcement on Friday. The company will discuss Contrave, the alleged wonder drug that the Food and Drug Administration eviscerated earlier this year, along with similar fat-fighting drugs from Arena Pharmaceuticals (Nasdaq: ARNA) and VIVUS (Nasdaq: VVUS). Still, that barest whisper of actual news was enough for investors to send shares soaring.

Obviously, they're expecting a big, positive development come Friday, but the Fool's Brian Orelli offers a more logical and compelling scenario. If the news is positive, it will point to a long road ahead for the drug. At the other extreme, Orexigen may be poised to pull its support for Contrave.

So why the big "if"? Well, Orexigen has a big shareholders meeting tomorrow, where the company will ask investors to triple its number of authorized shares. By not having to answer questions about Contrave until after the meeting, it will keep the vote from getting bogged down with concerns about why it's taking the drug so long to gain approval -- or whether Contrave will abandon its efforts altogether.

I bought into Orelli's negative thesis here, marking Orexigen to underperform the broad indexes in Motley Fool CAPS. I'm in the minority over there, since more than 82% of the members who've rated it think the company will beat the Street. Share your opinion on the Orexigen Therapeutics CAPS page, and let us know whether leading investors on like this portends good things.

Feeling energized
Its shares are trading hands at a rate two and a half times greater than average, and Lucas Energy thinks it knows why: Marathon Oil (NYSE: MRO) is buying up the Eagle Ford shale acreage owned by a joint venture partner of Lucas, and will be investing more resources to the oil play. Lucas also has a joint venture with Marathon at Eagle Ford.

The shale play has been growing in stature recently, with President Barack Obama identifying the Eagle Ford shale as a region crucial to our energy independence. With the government focused on the resources contained there, and a partner committing to doing even more, it's easy to see why Lucas Energy is booming.

Yet it's also flying under the radar of much of Wall Street and Main Street. No analysts cover the oil stock, and less than 100 CAPS members have weighed in on it. However, 88% of those that did also believe it will go on to outperform the market averages.

Yesterday's price action will likely bring Lucas to the attention of more investors. Keep an eye on the stock by adding it to the Fool's free portfolio tracker.

Making a connection
For a stock that's up more than 400% over the past year, VirnetX Holding's 11% jump yesterday might be considered just another day in the life of the 4G security software specialist. But the stock has been bouncing around over the past two months, making the straight-line trajectory it once followed now level off.

Speculation about just what its portfolio of 48 patents might be worth leads some to conclude that even at its current lofty levels, shares of VirnetX remain vastly undervalued. The $200 million settlement it wrangled out of Microsoft (Nasdaq: MSFT), if applied across all of its intellectual property, still portends a valuation almost double what it fetches now.

But some CAPS members are suspicious about VirtnetX's use of its patent portfolio as a weapon for growth. Members naughtyguy and bluedome express doubts about the effectiveness of the strategy, whatever the outcome of the Microsoft case was, but mntwst68 says that if it can pull off the same success against Google and the others it's targeting, then the plateau it hit was just the next launching pad for growth.

Dial up more opinions on the VirnetX Holding CAPS page, and stay on top of the company's developments by adding it to your watchlist.

Going into orbit
It pays to start your own research on these stocks on Motley Fool CAPS, where you can read a company's financial reports, scrutinize key data and charts, and examine the comments your fellow investors have made, all from the stock's CAPS page. Then you can decide for yourself whether your stock's headed for reentry, or off to infinity and beyond.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.