Charlie Munger blasts 'ridiculous' idea that Warren Buffett enriched himself at his shareholders' expense

• Warren Buffett is facing scrutiny after ProPublica reported on his personal stock trades.
• Charlie Munger dismissed the idea that Warren Buffett would enrich himself over his shareholders.

Warren Buffett is in the rare and uncomfortable position of having his ethics questioned following ProPublica's report on his personal stock trades, but Charlie Munger delivered an impassioned defense of his business partner to CNBC this week.

"I don't think there's the slightest chance that Warren Buffett is doing something that's deeply evil to make money for himself," said the 99-year-old vice-chairman of Buffett's Berkshire Hathaway conglomerate.

"He cares more about what happens to Berkshire than he cares what happens to his own money," Munger continued, pointing to Buffett's pledge to donate virtually all of his wealth to good causes.

Since 2006 the investor has gifted more than half of his Berkshire stock — which makes up more than 99% of his net worth — to the Bill & Melinda Gates Foundation and four of his family's foundations.

The idea that Buffett enriched himself at the expense of his shareholders is "not a plausible argument," Munger said. "It's one more ridiculous thing that's said about Berkshire."

CNBC's Becky Quick, who interviewed Munger, pointed out that he hadn't read the ProPublica story.

ProPublica, citing leaked IRS tax returns from 2000 to 2019, raised questions about Buffett's personal portfolio. It accused him of selling Wells Fargo, Walmart, and Johnson & Johnson shares worth a combined $80 million around the same time that Berkshire was buying or selling those three stocks.

The investigative-journalism nonprofit said the trades appeared to break the rules that Buffett himself imposed at Berkshire. Employees with inside knowledge of what the company is trading — or plans to trade — are barred from buying or selling those securities.

ProPublica also pointed out that Buffett has publicly said he avoids having securities in his personal portfolio that Berkshire holds or has in its sights, to avoid any potential conflicts of interest.

Buffett personally sold nearly $500 million worth of shares in the roughly 20-year period, and disposed of bonds worth much more, the outlet said.