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 30

Weekly Gain (NASDAQ:JD)



Ballard Power (NASDAQ:BLDP)






OmniVision Technologies (NASDAQ: OVTI)



Palo Alto Networks (NYSE:PANW)



Source: Barron's.

Let's start with China's leading consumer-direct retailer had a rather tame IPO a week earlier. It went public at $19 on May 22, closing out the trading week a day later at $20.10. Investors were able to ponder its prospects over the Memorial Day weekend, and emerged bullish this week. CLSA also helped things out by initiating coverage with a "buy" rating on Wednesday.

Ballard Power also won over the bulls. It moved higher after Stifel offered up a bullish note on one of Ballard Power's fuel-cell peers. The analyst's comments about improving cost profiles making fuel cells more compelling as a power source naturally apply to all players, but it's interesting to note that Ballard Power's stock moved nearly twice as high as the shares of the company that it was upgrading.  

MannKind continues to move higher ahead of an important regulatory approval milestone that could happen next month. MannKind is trying to get Afrezza -- its inhaled insulin solution -- to market. On Tuesday it announced that it would be presenting at three major health-care conferences through June. This follows a well-received shareholder meeting a week earlier and a Piper Jaffray upgrade the week before that.

OmniVision was a pretty picture after announcing blowout financials. The maker of image sensors may seen revenue dip slightly, but adjusted earnings soared 37% to $23.9 million, or $0.40 a share. There are challenges in the cutthroat market for camera chips, but OmniVision's ability to increase margins in this climate is applause worthy.

Finally we have Palo Alto Networks jumping after posting better-than-expected quarterly results. Revenue soared 49% to $150.7 million with an adjusted profit of $0.11 a share. Wall Street was holding out for net income of $0.10 a share on $146.2 million in revenue.

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