Can you tell when a company's stock is about to implode?

Few people, if any, have repeatedly shown the ability to accurately predict a massive decline in a company's shares. But I have five steps that might offer you some assistance.

History serves an important lesson
Back in 2000, investors were blinded by an Internet world that was growing at a phenomenal rate. Many experts jumped on the tech bandwagon, but Wharton professor and writer Dr. Jeremy Siegel was among a small, vocal minority that failed to hear the siren song.

Siegel openly critiqued many Internet companies and their overly generous valuations, including networking giant Cisco Systems. Cisco's shares went from a high of $80 in 2000 to lows of $10 two years later, turning an investment of $10,000 into a pittance of just $1,250. In fact, Cisco brought Siegel fame -- and perhaps infamy -- when he discussed the company on CNN's Moneyline:

It's a super company. I would probably buy it at 80 times earnings, but at 150 times earnings? We have six stocks in the top 20 [market value] over 100. We have had no history of this. Never have stocks been worth over a hundred times earnings once they've gotten to the size of these companies.

Remember when that happened?
The rest, as they say, is history -- and Cisco wasn't the only example. Other tech giants such as Oracle and Qualcomm (NASDAQ:QCOM) shed 60% or more. Siegel proved adept at identifying this dangerous trend, going on to write about it in The Future for Investors. While the book offers plenty of investing gems, I believe his five simple lessons for how to avoid losing money in a bubble are the most valuable:

  1. Valuations are critical.
  2. Never fall in love with your stocks.
  3. Beware of large, little-known companies.
  4. Avoid triple-digit price-to-earnings (P/E) ratios.
  5. Never short-sell in a bubble.

Two questionable calls
With an eye toward lessons 3 and 4, here are two stocks that may have gotten ahead of themselves:

Company

Market Cap (billions)

Trailing P/E

VMware (NYSE:VMW)

$24.9

111

SunPower (NASDAQ:SPWR)

$6.3

294

Now, these companies might just go on to defy the odds. But I suspect you'll want to be on your game in case they miss what are very optimistic expectations.

Look elsewhere
Instead, Siegel and other investing gurus suggest finding companies that don't carry rich valuations, have clear-cut business models, and offer more than just simple growth opportunities. But that's not all.

In his book, Siegel suggests that investors might want to look toward industries whose growth lags expectations, and whose existence is under the average investor's radar. Why? A successful company in an underperforming industry can also be explosively profitable because it will "maximize productivity and keep costs as low as possible" while simultaneously outliving competition. This translates to significant bottom-line appreciation.

Examine three small-cap stocks that have done just this in relatively sleepy industries:

Company

Industry

Market Cap (in billions)

3-Year Annual Return

Trailing P/E

Amedisys (NASDAQ:AMED)

Nursing Care

$1.4

27.8%

20

Middleby (NASDAQ:MIDD)

Commercial Ovens

$0.8

21.1%

15

PetMed Express (NASDAQ:PETS)

Pharmacy Benefits

$0.3

17.7%

16

Forget the hype
Chasing hot companies in hot industries will often leave you burned. In the long run, it's likely that a company's valuation will land squarely alongside its earnings capacity -- which is often unproven when a company sports a triple-digit P/E.

Instead, you'll be rewarded by buying shares of small companies in underfollowed industries that have demonstrated a real ability to make money. This is the strategy that we take at our Motley Fool Hidden Gems small-cap investing service and our recommendations are beating the market average by 22 percentage points.

You can take a look at the stocks Hidden Gems is recommending today by joining the service free for 30 days. Click here for more information.

Fool analyst Nick Kapur has no material position in any company mentioned above. Amedisys is a Stock Advisor selection. Middleby is a Hidden Gems recommendation. The Fool has a disclosure policy.