It's a new week, which means it's time to check the most interesting insider purchases. After reading through numerous filings using insider tracking tool Form 4 Oracle, here are my top five today.

The week's buying

Company

Closing Price 4/8/08

Total Value Purchased

52-Week Return

Apollo Group (Nasdaq: APOL)

$47.78

$533,260

10.5%

Chesapeake Energy (NYSE: CHK)

$47.95

$22,875,000

48.2%

ConAgra Foods (NYSE: CAG)

$24.49

$80,750

1.4%

H.B. Fuller (NYSE: FUL)

$21.31

$209,566

(23.2%)

Red Hat (NYSE: RHT)

$20.28

($3,414,090)

(7.3%)

Sources: Fool.com, Yahoo! Finance, Form 4 Oracle, SEC filings.

Buying at the Chesapeake
Chesapeake Energy CEO Aubrey McClendon is one of the best investors to ever appear in this column. Some of his notable purchases:

Most of the time, McClendon has been right. Spectacularly right, in the case of his 2007 purchases -- all 13 buys are currently in the money. And look at Chesapeake's return versus the S&P 500 since August of 2005. No wonder he's rich.

McClendon's record is such that I simply can't ignore him when he's buying. Neither, it seems, can our 95,000-strong Motley Fool CAPS community:

Metric

Chesapeake Energy

CAPS stars (5 max)

*****

Total ratings

3,461

Bullish ratings

3,370

Percent Bulls

97.4%

Bearish ratings

91

Percent Bears

2.6%

Bullish pitches

625

Bearish pitches

24

Data current as of 4/9/08.

Believers in this Inside Value pick abound. They've good reason. Last month, Chesapeake made an oil and gas discovery at its Haynesville, La., drilling site that McClendon described as "the most important operational announcement" in the company's 19-year history.

Collecting on the promise of that discovery won't be easy, and Chesapeake has issued some 20 million new shares to fund the project. That'd be pretty disappointing news for diluted investors if McClendon hadn't decided to buy a piece of the action for himself.

Actually, that doesn't quite capture it. Last Friday, McClendon made the biggest purchase I've yet witnessed in covering his buying over the past three years -- 500,000 shares for $22.9 million.

Imagine if he's right this time, too.

Look what's in my Red Hat!
Now for another chapter in our semi-regular series about how Form 4 filings can deceive you. Linux leader Red Hat, a company I love, draws the short straw this time.

A quick review of insider transactions at Yahoo! Finance shows that company controller Mark Cook bought 622 shares at $20.45 apiece one week ago. Trouble is, he also sold the same number of shares at $20.44 apiece.

Or did he?

Check the Form 4. Both the purchase and the sale are listed. But if you read the footnotes, you'll see that, really, not a dime changed hands. Quoting: "The sale and subsequent repurchase of shares was pursuant to an IRA rollover."

The lesson? When it comes to filings, footnotes are often everything.

There's your update. See you back here next week, when we dig through more insider filings in search of the next home run stock.

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Fool.com and Rule Breakers contributor Tim Beyers, who is ranked 16,115 out of more than 95,000 participants in CAPS, didn't own shares in any of the stocks mentioned in this article at the time of publication. H.B. Fuller is a pick at Motley Fool Hidden Gems Pay Dirt. The Motley Fool has a disclosure policy.