With shares of Apple ( AAPL) trading near an all-time high, CFO Peter Oppenheimer decided it was time to cash in.

Oppenheimer exercised 750,000 options last week, grossing a cool $32 million. And he's only the latest Apple executive to take advantage of the stock's latest bull run.

In recent months, at least four other senior company executives have cashed in 100,000 or more options, seeing millions of dollars' worth of gains.

The sales by Oppenheimer in particular could be something of a red flag, says Jonathan Moreland, director of research at InsiderInsights.com. It's not uncommon to see insiders exercise their options after a stock's had a strong run, but what's unusual is that Oppenheimer's sales have come in one big burst of activity, he says.

"The question arises, 'Why now?'" says Moreland, a contributor to TheStreet.com's sister site, RealMoney.com, who has no position in Apple.

But other analysts were less concerned. With Apple having performed so well in the last two years, many investors are likely to overlook some insider sales, says Todd Fernandez, a researcher at Glass Lewis, a proxy analysis and stock research firm.

"I don't see this as a red flag," says Fernandez. "These guys get a hall pass for a little bit of time."

Apple spokesman Steve Dowling declined to discuss Oppenheimer's reasons for selling. "It's great to see our management team get rewarded for their incredibly hard work by selling some of their stock," he said.

The sales by Oppenheimer and the other Apple executives are governed by 105b-1 trading plans, which typically state how many shares an executive plans to sell and give guidelines on when those shares will be sold.

But Apple has not disclosed the details of the trading plans, and Dowling declined to divulge them.

Oppenheimer's sales came as part of a series of transactions made beginning last Monday. They represented the first time Oppenheimer, who has been with the company since 1996, had exercised a significant number of options. The options he exercised were not in danger of expiring in the near future.

Apple does not list Oppenheimer as one of its top-paid executives or as one of its top shareholders, and therefore has not divulged his options holdings or his salary.

However, according to the filings he made last week, he holds only 14,143 shares of Apple stock outright, a pittance compared with the number of options he sold.

Other Apple executives who have exercised options recently include Avadis Tevanian Jr., the company's chief software technology officer; Ronald Johnson, senior vice president in charge of Apple's retail operations; Bertrand Serlat, senior vice president of software engineering; and Nancy Heinen, the company's general counsel.

Of those employees, Tevanian has sold the most stock and seen the biggest gains, cashing in 900,000 options since mid-August for a gross windfall of about $36.5 million.

But the others also saw significant gains. Johnson, for instance, cashed in 750,000 shares in August for a $22.6 million gain. In a series of sales dating from July to last week, Serlat exercised 140,000 options seeing a $5.1 million gain. And Heinen cashed in 125,000 options for a $4.7 million windfall.

Too Much Exercise?

For Johnson and Tevanian, who are both listed among Apple's top-paid executives, the options exercises amounted to more than 20% of the options they held at the end of the company's 2004 fiscal year.

While Johnson didn't exercise any options in fiscal 2004, Tevanian cashed in 700,000 options that year for a gross gain of $8.8 million, according to Apple's filings.

Regardless, for both Johnson and Tevanian, the recent options exercises represent a huge windfall compared with their cash compensation. Johnson, for instance, had a base salary of $484,836 in fiscal 2004 and received a cash bonus of $1.5 million.

Tevanian received a base salary that year of $469,681 and got a mere $1,500 cash bonus.

The exercises succeed Apple stock's rocket rise. Shares are up 75% in the year to date and nearly 400% over the last two years. Over that time, Apple's revenue and earnings have swelled, thanks to booming sales of the company's iPod digital music players.

Still, the exercises offer a window into executive compensation practices at the company, which has been one of the more prolific dispensers of options among public companies.

In fiscal 2004, for instance, Apple awarded a net grant of 15 million options, or about 4% of its outstanding shares at the end of the previous year. At the end of fiscal 2004, Apple had outstanding options representing about 14% of the company's share count.

The gross quantity of options being sold by insiders should be balanced against the stock's big run, says Darren Chervitz, research director at Jacob Asset Management, which is long Apple. As for Jacob, the firm isn't all that concerned about the sales, because Apple represents only a small position for the fund.

However, "If Apple was one of our top 10 holdings, I would be lot more concerned about significant insider sales," Chervitz says.

In addition, insider sales aren't necessarily predictive of the longer-term outlook for a stock, says Mark LoPresti, who tracks insider sales as a senior quantitative analysts at Thomson Financial.

Not only has Apple's stock done well in the last two years, but also it has strong momentum behind it, underlined by strong earnings growth and well-received, new product launches, he says.

"You have to be cautious when you look at insider activity," says LoPresti. "It's usually perilous to sell stocks with high momentum on the basis of insider selling."

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