It was a rocky week on Wall Street, with Nasdaq stocks inching lower and the Dow inching higher, but there were plenty of stocks really making some serious moves. Let's take a closer look at five of this past week's biggest scorchers.


May 16

Weekly Gain

Rackspace (NYSE:RAX)












Hyperdynamics (NYSE:HDYN)



Source: Barron's.

Let's start with Rackspace. The provider of Web hosting for sites and cloud computing applications took off after hiring Morgan Stanley to explore strategic alternatives that may result in a sale of the company. Rackspace has been struggling lately as dot-com giants engage in cutthroat pricing, using their server farms as loss leaders to secure additional working relationships. It also helps Rackspace that it posted better-than-expected financial results earlier in the week. 

Gogo also took off after flying past Wall Street's targets. The leading provider of in-flight Wi-Fi saw revenue climb 35% during the quarter, with adjusted EBITDA growing even faster. Gogo had tumbled earlier this month when AT&T announced that it will enter this market that allows airlines to offer connectivity to passengers during flights. 

MannKind took more than one small step after Piper Jaffray changed its bearish tune. Analyst Dr. Joshua Schimmer upgraded the company championing an inhaled insulin solution from "underweight" to "neutral." Schimmer realizes that he blew it in calling for a negative FDA panel review for MannKind's Afrezza. Now the chances are strong that MannKind will clear approval and have a partnership in place by July. 

CalAmp marched back into fancy after a pair of analysts took advantage of recent price weakness to push out positive notes. FirstAnalysis upgraded shares of CalAmp from "neutral" to "overweight" with a $23 price target. A day later it was Stephens initiating coverage with a similar "overweight" rating. Its price target for CalAmp rests at $25.

Finally, we have Hyperdynamics shooting higher on Friday after announcing a settlement in a subsidiary's litigation with AGR Well Management in relation to project management services provided a couple of years ago in connection with the drilling of a well in offshore Guinea. Hyperdynamics' subsidiary will receive $17.7 million -- or net proceeds of $15.6 million -- that was tied up in an escrow account.

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Rick Munarriz owns shares of MannKind. The Motley Fool recommends Rackspace Hosting. 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.