Warren Buffett admitted a 'big' mistake, touted Berkshire Hathaway's past deals, and cautioned traders in his annual letter

• Warren Buffett published his annual letter to shareholders on Saturday.
• The Berkshire Hathaway CEO made a "big" mistake in overpaying for Precision Castparts.
• Buffett reminded stock traders that their transaction fees go straight to Wall Street.
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Warren Buffett owned up to a major mistake, trumpeted Berkshire Hathaway's past successes, and drew a line between his long-term shareholders and the meme-stock crowd in his annual letter on Saturday.

The billionaire investor said Berkshire's focus is boosting operating earnings and making large, high-quality acquisitions. His conglomerate "met neither goal" in 2020 as its operating earnings slumped 9% and it failed to close any major deals, he said.

Moreover, Buffett admitted to overpaying for Precision Castparts, the aerospace-parts manufacturer that Berkshire purchased for $37 billion in 2016. The price tag was a "big" error that fueled an "ugly" $11 billion writedown last year, he said.

Buffett dedicated most of his letter to reflecting on some of Berkshire's most famous investments. See's Candies, Geico, National Indemnity, Nebraska Furniture Mart, and Clayton Homes all received a mention.

The 90-year-old investor argued their US origins were a key factor in their success. "These builders needed America's framework for prosperity," he said. "Our unwavering conclusion: Never bet against America."

Buffett didn't miss the chance to highlight that Berkshire owns $154 billion in US-based assets such as factories and equipment - more than any other US company. AT&T is the runner-up with $127 billion worth, he said.

The Berkshire chief also discussed his shareholder base. He emphasized the "special kinship" he feels to the million-plus individual investors who trust him with their money and embrace Berkshire's culture of partnership.

Buffett made a distinction between Berkshire's long-term shareholders and people who buy into the hype around the likes of Tesla, GameStop, and Bitcoin. He reminded traders that the fees they pay to constantly tweak their portfolios flow straight into Wall Street's pockets.

"The tens of millions of other investors and speculators in the United States and elsewhere have a wide variety of equity choices to fit their tastes," Buffett wrote. "They will find CEOs and market gurus with enticing ideas."

"If they want price targets, managed earnings and 'stories,' they will not lack suitors," he continued. "'Technicians' will confidently instruct them as to what some wiggles on a chart portend for a stock's next move. The calls for action will never stop."

Finally, Buffett revealed that his 97-year-old business partner and Berkshire's vice-chairman, Charlie Munger, will join him on stage at Berkshire's shareholder meeting in May.

The event will be held in Munger's home state of California, after he decided not to fly to its usual Nebraska location last year due to the pandemic.