There's never a shortage of stocks going the wrong way in any given chunk of time. No stock goes straight up, and sometimes fundamentals can get a bit wobbly. Let's take a closer look at five of this past week's biggest sinkers.

Company

May 23

Weekly Loss

Provectus Pharmaceuticals (PVCT 1.24%)

$2.02

35%

Aeropostale (AROPQ)

$3.41

23%

Dick's Sporting Goods (DKS -0.85%)

$43.08

16%

LifeLock (LOCK)

$11.34

13%

Walter Energy (WLTGQ)

$5.69

10%

Source: Barron's.

Let's start with Provectus Pharmaceuticals. The biotech specializing in treatments for oncologic and dermatologic conditions shed more than a third of its value after a report claimed that its flagship therapy was being denied Breakthrough Therapy Designation by the FDA. Provectus refuted the claims, but the stock was halted all day on Friday as regulators did in fact deny it the expedited designation.

PV-10 -- Provectus' investigational metastatic melanoma therapy -- seemed promising after encouraging phase 2 trials two years ago. It just doesn't help its credibility to deny something two days before it backfires, even if its points refuting patent expirations and associations with stock promoters hold up. 

Aeropostale ran into some turbulence after warning that its second-quarter loss would be larger than expected. The once trendy mall retailer has been struggling, posting six consecutive quarterly losses that will be going on seven soon. RBC Capital Markets downgraded the stock on the grim report.

Dick's Sporting Goods had a hard time attracting hunters so it became the prey. The sporting goods retailer took a hit after posting disappointing results. Weakness in golfing and hunting were to blame for Dick's hosing down of its full-year earnings and comps targets.

LifeLock slumped after pulling its mobile wallet app on security breach concerns. LifeLock had recently purchased the mobile app developer, and clearly your reputation as a protector of identity theft is going to take a hit if your app fails on that front. Goldman Sachs downgraded the stock on the news, while Sterne Agee and Pacific Crest lowered their price targets.  

Finally we have Walter Energy with a lump of coal in its stocking. Coal stocks got hammered after a Politico report claimed that the EPA was going to introduce anti-carbon regulations on June 2 that would require utilities to scale back on their coal consumption. Earlier this month, Stanford University turned heads by announcing that it will divest from coal companies.