Carl Icahn is 77. Big deal

Carl Icahn
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Carl Icahn

At 77 years old, Carl Icahn is at the most active and successful point of his long-storied career on Wall Street. And despite his very public battle with Michael Dell, the barbarian has traded in his activist axe for a Warren Buffett-like investment style and now sports a comfortable beard.

Over the last four years, Icahn has taken an ownership stake in 22 companies, more than any four-year period for him since at least 1994, according Netflix is up more than 500 percent since his stake became public in October.

So what's driving Wall Street's already richest man to keep going? Perhaps by staying at it for this long, he's proving to his critics that he is—in fact—not in it just for the money. The septuagenarian is sending a message that he was, and always will be, about the corporate governance ideal he holds so dear.

"I think he's looking at these companies with all their huge cash balances and zero interest rates and saying to lazy executives, 'Get off your ass and do something,'" said Pete Najarian, co-founder of "These companies are not broken. They are just sitting on their hands."

(Read more: Dell vote will have investors on edge)

Of course, it helps that nowadays, Icahn is managing just his own money, after returning all outside capital in 2011 following some big financial crisis losses. Forbes estimates his worth at more than $20 billion. That's a lot of dry powder for such an active mind that sometimes decides to take a billion dollar position in a company after simply reading an article in the paper.

"It's because of all his money," said Ken Squire, who's racked up a good track record for himself by following Icahn and others for his 13D Activist Fund. "He's feeling the freedom and that allows him to be more creative."

By Squire's math, following Icahn's buys and sells over the last 20 years would have netted you a 39 percent annualized return, compared with just an 8.6 percent return for the S&P 500. And those returns have accelerated as of late.

CVR Energy, Greenbrier, Hain Celestial, Take Two and Motorola Mobility are among the best stock picks for Icahn over the last four years.

"Carl gets a lot of attention for his confrontational activism and removing directors and CEOs, but some of his best investments are companies where he believes in management and the CEO and may or not take a board seat to support them," said 13D's Squire.

As mentioned above, Netflix is the biggest winner of all, and Icahn hasn't shown any indication of wanting a seat on the board. (Of course, his 10 percent stake would give him a shot at getting one if the streaming video company were to stumble).

Reed Hastings, CEO of Netflix, told Forbes in March, "I was worried about him when we didn't know him, but I now must say that I enjoy his company."

Icahn Enterprises (IEP), the publicly-traded vehicle for his hedge fund, is coming off one of its best quarters ever, with hedge fund assets up 10 percent.

"We believe the current environment sets up well for IEP's activist strategy, given large corporate cash balances and favorable financing markets," wrote Jefferies analyst Daniel Fannon in a May report. He rates the stock a "buy."

But Icahn hasn't totally given up the Far Rockaway, Queens-swagger that led to big fights with TWA Airlines and Nabisco two decades ago. His bruising battle with Michael Dell over the founder's namesake company grows more contentious by the day.

The company is even considering delaying this week's shareholder vote on Michael Dell's buyout as Icahn gains more and more supporters among big-name holders like T. Rowe Price's Brian Rogers.

"If our board is elected, Michael Dell will not be running the company," Icahn told CNBC in May.

Michael Dell is "stealing the company," and his justification is like something "out of Saturday Night Live," Icahn said.

And, of course, there is the fight heard 'round the trading world: his battle over Herbalife with the much younger activist Bill Ackman via phone on CNBC in January. Ackman has a monster short position in the supplement maker because he believes the multi-level marketer is a pyramid scheme preying on the poor.

(Read more: Dell buyout vote could be postponed)

Icahn sees it differently, but it's not exactly clear why. It seems part of his reasoning is that he doubts the government will act to shut down Herbalife based on Ackman's claims. But the fight includes a personal beef with Ackman himself.

During a contentious 45-minute interview on CNBC that elicited vocal reactions from traders on the NYSE floor, Icahn referred to Ackman as a "crybaby" and stated "I wouldn't invest with you if you were the last man on earth."

Personal or not, Icahn and his 17 percent stake is winning the financial battle so far, as shares of Herbalife are up 60 percent this year alone.

So when Icahn makes the rare departure from his office in the GM building in Manhattan for the short walk over to CNBC's Delivering Alpha conference, there will be an anxious crowd waiting on his every word.

Is he sticking with Netflix and Herbalife? Will he raise his Dell bid? When will he retire? And how does he like the beard?

—By CNBC's John Melloy and Scott Wapner. Follow them on Twitter @CNBCMelloy and @ScottWapnerCNBC.