Watching insiders is like participating in a weeks-long stakeout. You expect something to happen, but you don't know what. So you settle in, sip your coffee, and wait for clues to solving the big case.

Here, the "case" is direction: Which way is your stock headed? The "clues" come in the form of insider buying and selling action. Have a look at Caterpillar (NYSE:CAT) over the past year.

Insider Rating

Bullish
Shares just 16% off a 52-week high, yet limited sales suggest there may still be room for this stock to run.

Business Description

One of the world's largest suppliers of construction and other heavy industrial equipment.

Recent Price

$51.60

CAPS Stars (Out of 5)

****

Percentage of Shares Owned by Insiders

0.25%

Net Buying (Selling)*

($207,898)

Last Buyer (% Increase)

William Osborn, director
2,000 shares at $39.86 apiece on May 6
(Purchase bolstered direct holdings by 8%)

Last Seller (% Decrease)

Douglas Oberhelman, Chief Accounting Officer
20,000 shares at $38.71 apiece on Nov. 3, 2008.
(Sale represented 22% of direct holdings)

Competitors

Deere (NYSE:DE)
CNH Global (NYSE:CNH)

CAPS Members Bullish on CAT Also Bullish on

General Electric   (NYSE:GE)

CAPS Members Bearish on CAT Also Bearish on

Ford (NYSE:F)
Bank of America (NYSE:BAC)

Recent Foolish Coverage of CAT

4-Star Stocks Poised to Pop: Caterpillar
Great Call on Caterpillar! What's Next?
Caterpillar Gets Squashed

Sources: Form 4 Oracle, Capital IQ, and Motley Fool CAPS. (Data current as of Sept. 29.)
* Open market sales and purchases only.

What we're tracking here, and why
Insider buying data can be confusing. Here, I'm concentrating only on buying and selling conducted in the open market. With most of these transactions, insiders control the timing. Other times they're buying or selling under the purview of a 10b5-1 plan. Either way, personal holdings are being bought and sold.

Those personal holdings matter the most -- they're the shares executives hold for investment, rather than compensation. Employee stock options are different; they're compensatory in the purest sense. I've stripped out options-related buying and selling from the calculations you see above.

The Foolish view: Bullish
Construction hasn't exactly been in a boom cycle lately. The Architectural Billings Index fell to a three-month low in August, suggesting that there's still a long way to go before we see a full recovery in nonresidential construction.

That's bad news for Caterpillar and building equipment peers such as United Technologies (NYSE:UTX). They're at their best when supplying the needed heft for large-scale, nonresidential projects. Yet despite the bad news and generally sagging global economy, the stock has been a massive market-beater over the past quarter.

CAPS investors expect the good times to continue. "Global (China) business will help in short term, but I think if [and] when the U.S. economy really picks up that CAT will see huge growth over the next 3 to 5 years," wrote CAPS investor toms66gtstang last week. "I'm in with a small position at $26.40 so I'm feeling pretty good already, just wish I had bought more."

Insiders are at once more bearish and more bullish than toms66gtstang. Most of their buying has come at more than $30 per share, and what selling they've done has come near $40 per share. Yes, the stock trades for higher than that today, but not that much higher. Barring further insider sales, I predict a market-beating performance over the next 12 months.

Do you agree? Disagree? Log into Motley Fool CAPS today and tell us how you would rate Caterpillar.

And if you want me to take a Foolish peek at the insider action of your favorite stock, email me here or use the comments box below. I'll write this column as often as you, our readers, demand.

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