Over more than two decades, Nelson Peltz bought businesses, polished them up and sold them again a few years later, often racking up hefty profits.

Now, instead of purchasing companies outright, the billionaire investor is buying small stakes in them and pushing for change. And he's doing so through a newly created hedge fund that has raised more than $1 billion.

Since launching this venture in November, Mr. Peltz has pressed for a change in strategic tack or board seats at CBRL Group Inc., owner of the Cracker Barrel restaurant chain; fast-food restaurant operator Wendy's International Inc., and food producer H.J. Heinz Co. So far, CBRL and Wendy's have given in to some of his demands; A battle at Heinz has yet to play out.

The foray into hedge-fund activism has put Mr. Peltz back in the Wall Street spotlight, reviving memories of investing successes dating back to the junk-bond era of the 1980s -- as well as scrapes with his own shareholders that have some on Wall Street questioning his activist credentials.

Mr. Peltz's changed modus operandi reflects the popularity among large shareholders of taking matters into their own hands to boost returns. Despite slowing flows of money into once red-hot hedge funds, investors still want to ride along with a marquee-name manager.

Investors looking to join Mr. Peltz's crusade must be willing to carry a heavy burden: His hedge-fund outfit, Trian Fund Management LP, requires minimum investments of $25 million, according to a person familiar with the firm. That's a hurdle even for hedge funds, lightly regulated partnerships that often require their wealthy clients to pony up at least $1 million.

Plus, Trian's investors have to keep their money with the firm for three years, this person said. Such lockups are becoming more common -- in some cases because they allow the funds to avoid new Securities and Exchange Commission oversight rules -- but many investors still balk at losing control for so long.

Mr. Peltz and longtime business partner Peter W. May, who is also a principal in Trian, declined to comment on the firm.

Besides Trian, the pair controls about 40 percent of Triarc Companies Inc., the publicly traded company they have used for deals since 1993. Triarc is considering a restructuring that would see Messrs Peltz and May, along with Triarc's vice chairman, Edward P. Garden, relinquish executive roles. This would allow the three to focus on the hedge-fund firm, in which Mr. Garden is also a principal. Triarc last year invested $75 million in the venture.

The 63-year-old Mr. Peltz first gained attention in the 1980s, when he used junk-bond financing arranged by Drexel Burnham Lambert to purchase National Can Co. and then American Can. He merged the packaging companies and within three years sold them to France's Pechiney SA, snaring about $800 million profit on his total investment.

The association with Drexel earned Mr. Peltz the label of corporate raider. He is often mentioned in the same breath as Carl Icahn, a raider from that era who is now an activist hedge-fund manager. Yet people who know the two say their approaches differ.

"I would describe Carl as a trader who became a businessman and Nelson as a businessman who became an investor," says Jack Wasserman, an attorney in private practice who sits on Triarc's board and who has sat on boards of companies Mr. Icahn was involved with.

Mr. Peltz is best known for the 1997 purchase of beverage maker Snapple for $300 million. After a three-year turnaround, Triarc sold Snapple for about $1.45 billion.

Still, some on Wall Street eye Mr. Peltz warily, recalling his battles with his own shareholders.

The financier's sale of the can companies in 1988, for example, resulted in lawsuits from investors who claimed Mr. Peltz unfairly bought them out just months beforehand. Mr. Peltz denied the allegation but eventually settled, without admitting any wrongdoing, for $75 million. Pechiney paid half the amount.Messrs. Peltz and May also were censured by the London Stock Exchange in 1991 for their handling of a sale of shares in Mountleigh Group PLC. The two had taken a 20 percent stake in the property developer in the hope of using it for European takeovers, but the company eventually collapsed.

In 1993, Messrs. Peltz and May bought a stake in near-bankrupt DWG Group, a conglomerate that owned Arby's restaurants and the RC Cola brand, among other disparate businesses. They renamed it Triarc and focused on food and beverages businesses. This led to the Snapple purchase in 1997. A year later, in the midst of that turnaround, Messrs. Peltz and May proposed taking the company private. With Triarc's shares well below that year's high, shareholders cried foul and the plan fell through.

Triarc is still the franchisor of Arby's and owns more than 1,000 of the chain's 3,500 restaurants, along with interests in other, unrelated businesses. Under Triarc's proposed restructuring, those businesses may be spun off to shareholders.

Messrs. Peltz, May and Garden had been kicking around the idea of starting a hedge fund for at least the past two years, according to the person familiar with the fund. Mr. Peltz had long been frustrated by the constraints of working through a publicly traded vehicle due to restrictions on the number of investments he could make.

The idea clicked when hedge funds' surging popularity made investors more open to restrictive terms such as multiyear lock-ups of capital. That was key for an activist strategy because investors can't flee during often fierce public battles, the person says.

Although the fund has taken positions in industries Mr. Peltz knows best -- food and restaurants -- he plans to target companies in a variety of sectors, the person says.