Why Two Billionaires Like This One Stock

Looking for a stock pick?

Two billionaire investors who appeared on CNBC's "Squawk Box" last week said they have one.

(Watch: "Squawk Box" Newsmaker Interviews On-Demand)

Keep in mind, their investment companies collectively hold nearly 15 percent of the company, Legg Mason.

Activist investor and board member Nelson Peltz gushed last Thursday about the Baltimore, Md.-based asset management firm — two days after value investor Mario Gabelli said it would double.

Peltz — whose Trian Partners holds a 9.5 percent stake in Legg Mason — also said, "My money is on Mario. I would never bet against Mario."

Gabelli's Gamco Investors disclosed last week that it increased its stake in the asset manager to 5.2 percent.

He explained his thesis on Legg Mason a week ago, by pointing to the company's buyback plans and saying, "[It's] in the investment business, great cash generator, and they're solving a lot of their issues."

(Read More: Besides Legg Mason, Here's Another Stock Gabelli Thinks Will Double )

One of the issues the company resolved recently was dropping the word "interim" from CEO Joseph Sullivan's title. Peltz voiced his approval, saying Sullivan is "fantastic" and going to do a "terrific job."

As for the stock market at-large, the Trian chief said, "We're not stock market buyers. We're buyers of a few companies that we like and that we think that we can have some positive input with."

(Read More: Thursday's Big Deals Just the Beginning of M&A Boom: Peltz)

One of those companies is Family Dollar — a firm Peltz had tried to takeover a couple years ago. His investment partner Edward Garden has been on the company's board since the fall of 2011.

Peltz raved about the retailer. "[It's] had same-store sales increases for 20-plus years. … They've adapted well. And I think you're going to see continuing success."

He told CNBC he bought Family Dollar in the $30 range: "We believe in the company. We like it."

Peltz also expressed optimism about Ingersoll-Rand, whose products aim to enhance its customers' energy efficiency, productivity, and operations.

"We're involved in Ingersoll-Rand," said Peltz, who joined the company's board last summer.

"You saw that they made some initial moves there," he added, such as spinning off their security business, increasing the dividend, and buying back shares. "We think there's wind at their back, and we're very happy with what we're seeing."

By CNBC's Matthew J. Belvedere; Follow him on Twitter @Matt_SquawkCNBC

Additional News: This Is Just the Beginning for M&A Deals: Peltz

Additional Views: Here Are Two Stocks That Will Double: Mario Gabelli