Former hedge fund manager Whitney Tilson has called Berkshire Hathaway (NYSE: BRK.A) the to retirement stock. Tilson, who now writes for Empire Financial Research, issued a note this week praising Warren Buffett’s firm as the “No. 1 Retirement Stock in America.”

“Importantly for all investors — and especially retirees — it’s incredibly safe,” Tilson wrote. “It’s an incredible collection of high-quality businesses, run by the greatest investor of all time, and has the ultimate Fort Knox balance sheet.”

Berkshire has an extensive list of holdings right now. It is a large shareholder of Apple Inc. (NASDAQ: AAPL), Bank of America (NYSE: BAC), American Express (NYSE: AXP), Wells Fargo (NYSE: WFC), Kraft Heinz (NYSE: KHC), and Delta Airlines (NYSE: DAL). Tilson argues that Berkshire stock is cheap. He says that it trades at a 20% discount to his perceived intrinsic value.

Whitney Tilson on Berkshire

Tilson went on to say: “While Berkshire may not be as cheap today as it has been during times of market extremes, it’s still extremely attractive in light of the fact that we’re more than a decade into a complacent bull market, in which most stocks are trading at full (if not overly full) valuations.”

Tilson noted that the firm is also likely to boost stock buybacks in the near future.

“In his annual letter, Buffett is clear that he’s looking to buy back a lot more (he’s never before been so specific about who shareholders should call if they want to sell their stock to the company),” Tilson wrote.

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