Warren Buffett, Charlie Munger, and Bill Ackman just revealed striking changes to their stock portfolios. Here's a roundup of 6 key trades.

Warren Buffet, Bill Ackman, and other elite investors have recently revealed changes to their stock portfolios.

The Big Short investor Michael Burry, Charlie Munger, David Einhorn, and Jim Simons have disclosed changes to their holdings.

Here's a roundup of their newly revealed trades:

Mike Segar/Reuters

Greenlight Capital disclosed a bearish bet against the electric-vehicle company in the fourth quarter.

Greenlight bought put contracts against 100,000Tesla shares. The clean-energy stock has plummeted this year, meaning Einhorn could be sitting on a good profit if he hasn't exited the position.

The worst-performing holding of Einhorn's fund in 2020 was the stock ofTesla, which skyrocketed more than 700%. The investor wrote in his fourth-quarter client letter that he owned the shares at a silly price.

Reuters/ Allen Fredrickson

In late January, Bill Ackman disclosed a major bet on the stock.

The hedge fund only bought the shares this year, so they didn't show up in the fourth-quarter portfolio update. After the streaming giant's earnings tanked, Ackman pounced, snapping up 3.1 million shares in four days.

Ackman prefers to own more traditional businesses such as Domino's Pizza and Lowe's rather than technology stocks. The value investor explained that he was a long time fan of Reed Hastings, and was impressed by the company's subscription model, pricing power, vast content library, and other strengths.

AP Photo/Nati Harnik

In the fourth quarter, the Daily Journal borrowed more money and put the entire amount into an undisclosed stock.

The chairman of the Daily Journal and his business partner sold $50 million worth of stock in December, marking a 15-fold return on a $3.3 million cost base.

Munger combined the $37 million from Daily Journal's margin-loan account with the proceeds to plow $87 million into other securities.

In December, the Daily Journal suffered $30 million in losses. Many of Munger's followers were surprised by his use of margin, given his warnings about investing borrowed money.

When asked about the wager during the Daily Journal's annual meeting this week, Munger replied "We don't mind a tiny bit of margin debt."

The CEO of Business Insider is a member of the board.

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