Insider buying can be a bullish indicator for a stock, and it provides another piece of information for investors to weigh when doing investment research. Each week, I take a look at the largest insider purchases in search of investing opportunities with this often positive indicator.

Company Name

Market Cap

No. Shares Purchased

Value Shares Purchased

CAPS Rating  
(out of 5)

GeoEye (Nasdaq: GEOY) $971 million 40,000 $1.78 million ****
Monsanto (NYSE: MON) $30.9 billion 18,000 $1.01 million ****
Chesapeake Lodging Trust (NYSE: CHSP) $315 million 39,000 $634,000 *****
Intel (Nasdaq: INTC) $110.6 billion 20,000 $385,000 ****
General Electric (NYSE: GE) $171.4 billion 20,553 $334,000 ****

Sources: Barron's; Yahoo! Finance; Motley Fool CAPS.

Cerberus Capital Management bought another $1.78 million in GeoEye shares. The private equity firm has been buying stock in the company steadily over the last couple of months, amassing nearly 2 million shares. As an owner of more than 10% of GeoEye, Cerberus must report its transactions to the SEC. GeoEye provides satellite images to government and commercial customers for national security, mining, and agriculture-related applications. Shares of the company are near an all-time high, having risen 58% so far this year, boosted in part by the company's recent win of a $3.8 billion, 10-year contract with the National Geospatial Intelligence Agency.

Monsanto CEO Hugh Grant bought more than $1 million of the company's stock for $56.36 per share. Grant's purchase was his second large buy in recent months; he snapped up $1.95 million of shares in July. The stock is down 34% from its 52-week high and has underperformed the S&P 500 over the last year. Investors are concerned about the performance of the company's newest corn seed and its herbicide, Roundup.

Four board members plus the CEO of hotel REIT Chesapeake Lodging Trust bought shares at $16.25 apiece during a company stock offering. The company had its initial public offering in January, and has since bought four hotels.

Other notable insider buys include purchases by an Intel director and the company's CFO, as well as the head of GE Capital. Intel and GE are both down around 18% from the 52-week highs they reached in the spring. With GE, Michael Neal's purchase is particularly intriguing, since the GE Capital division has been the source of much of the company's difficulties since the financial crisis.

While Fools should do their own due diligence, rather than blindly following the insiders, insider buying can point to good places to look for opportunities.

For more on the companies mentioned, see: