Corporate earnings and continued doubt about Europe's finances helped wipe out the Dow yesterday, which tumbled 83 points after having started off the day in positive territory. Yet some companies managed to do even worse and plunged lower by double-digit percentages.

But let's see whether they had good reason to drop; panic-fueled declines can sometimes make for excellent buying opportunities.

Company

Yesterday's % Change

Price

CAPS Rating (out of 5)

MAKO Surgical (Nasdaq: MAKO) (43.1%) $14.01 *****
James River Coal (Nasdaq: JRCC) (24.7%) $2.16 **
Questcor Pharmaceuticals (Nasdaq: QCOR) (21.8%) $45.07 ***
Beazer Homes (NYSE: BZH) (11.8%) $2.98 *
Advanced Micro Devices (NYSE: AMD) (11.2%) $4.99 **

Building a bridge to nowhere
Count me among the skeptics who don't believe the housing industry is on the cusp of a recovery yet. Homebuilders might want to use that theory as justification for raising cash, as Beazer Homes did yesterday, but there are simply too many problems in the marketplace to suggest homebuying is going to take off. Beazer said it will sell $75 million in stock and 3 million equity units made up of a prepaid stock purchase contract and an unsecured senior note due in 2015. Hovnanian's already been out there raising cash and KB Homes is expected to move next. I'd use any bounce in a builder's price to bet against it. Unless and until the economy improves, housing will only see the occasional bright spot amid storm clouds of gloom.

So deep it's a gouge
Chip maker Advanced Micro Devices was one of those tech stocks that took down the Dow, reporting revenue and earnings forecasts that showed dismal expectations of PC sales. Along with other tech heavyweights like Applied Materials that offered up gloomy prospects of weak foundry demand, the tech sector was the albatross around the market's neck.

Caught by the short hairs
Noted short-seller Citron Research has often published spot-on attacks on sham outfits, particularly Chinese reverse-takeover stocks, but analysts said the report it issued on Questcor Pharmaceuticals that caused the company to lose a fifth of its value wasn't the best work it's published. The allegations leveled against the pharma's drug, Acthar, were old and misleading, according to the analysts at Jefferies Group. Citron doesn't often shoot blanks, but with Acthar's June sales soaring, I expect we'll see a lot of the lost ground recovered.

Between a rock and a hard place
Last month Standard & Poor's downgraded the credit rating of coal miner James River Coal as industry conditions worsened. And worsen they did. Amid a stalling global economic recovery, weakening demand for met coal, and cheap domestic natural gas prices making utilities switch to the cleaner-burning fuel, Patriot Coal filed for bankruptcy protection. With James River's own finances in doubt, the market pummeled the coal miner, expecting that it will be the next to succumb to the all-out assault being waged against it. Keep an eye on whether this development leads to a domino effect or if it proves to be a rallying point for coal.

Keep swimming or die
Management is fond of pointing to timing issues when it comes to explaining away a fall off in sales, but investors can clue in to the veracity of such statements by checking out how strong the guidance is they offer for next month. If demand is truly strong and temporary ordering issues from customers are really at the heart of the matter, then the next quarter's results should enjoy the benefit of the extra sales falling into its range. But if guidance remains the same or comes in even weaker, than having a dim view of management's explanation is probably the right course of action.

Which is where we find MAKO Surgical, the manufacturer of orthopedic surgical systems, who blamed timing problems for a lousy quarter but didn't up next quarter's guidance. As a result, it seems that sales are falling more because of a lack of demand than not enough days in the quarter.

The huge sell-off in MAKO's stock certainly makes it appear to be a tempting way to play on an overreaction by the market, but this might not be an overreaction after all. It looks more like a business that has some serious issues facing it. One quarter of disappointing sales can be forgiven, but when a company racks up several in a row -- as MAKO has -- then investors need to be more circumspect in their selections.

It's been down this road before, and I'm not closing out my outperform rating on CAPS just yet, but I'm also not sure I'd be racing in to buy just yet, either. Companies are like sharks -- they have to keep swimming forward or they die. MAKO needs to bounce back here, although investors like CAPS member arembr01 believes there are times you need to cut and run: "After the second round of coming up short, I think I'm going to cut my losses and walk away."

Tell me on the MAKO Surgical CAPS page or in the comments section below whether you agree it can still beat the Street or, like me, think it's just a matter of time before it crashes and burns.

Ready for a resurrection
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