'Washed up' Warren Buffett has supposedly lost a step. The investor has scored an $11 billion gain on Apple this year.

• Warren Buffett is being fiercely criticized, despite scoring an $11 billion gain on Apple this year.
• President Trump said the Berkshire Hathaway boss made a mistake when he dumped his airline shares in April, while trader David Portnoy said Buffett is "washed up" and has "lost his fastball."
• However, Buffett is still doing some things right.
• Apple stock hit a record high on Tuesday, meaning the value of Berkshire's stake has jumped by about 15% this year to $83 billion.
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Warren Buffett has been a popular punching bag in recent weeks, even though the famed investor's biggest holding — accounting for more than 40% of his portfolio — has gained $11 billion in value this year.

President Donald Trump said Buffett made a mistake when he sold his airline stocks in April. Billionaire investor Ken Fisher suggested the 89-year-old's age might explain why he didn't go on a buying spree during the coronavirus sell-off.

"Time to reinvent yourself, Warren," investor David Merkel said, arguing that Buffett had an "outdated view" of how far the stock market would fall. David Portnoy, the Barstool Sports founder and celebrity trader, tweeted that Buffett was "washed up" and had "lost his fastball."

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Buffett's Berkshire Hathaway also lost billionaire Bill Ackman as an investor after it didn't deploy its huge cash pile during the downturn. Ackman argued his Pershing Square hedge fund could be more nimble than the conglomerate due to its smaller size.

Despite the intense criticism, Buffett has done at least one thing right. Berkshire owned more than 5.5% of Apple at the end of March, according to Securities and Exchange Commission filings, making it the tech titan's second-biggest shareholder.

Apple's stock price hit a record high this week, boosting the company's valuation to almost $1.5 trillion, and the value of Buffett's stake to north of $83 billion as of 11:15 a.m. ET on Tuesday.

Berkshire's Apple stake was worth about $72 billion at the end of December, meaning it has scored a gain of more than $11 billion on a single stock — which happens to make up more than 40% of the value of its stock portfolio — in a matter of months.

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Similarly, Berkshire held about $993 million worth of Amazon stock at the end of December, SEC filings show. The e-commerce titan's shares also climbed to a record high this week, lifting the value of Berkshire's stake to nearly $1.4 billion, even after it cashed out 4,000 shares or about 0.7% of the position in the first quarter.

True, several of Berkshire's largest holdings — including Bank of America, Coca-Cola, American Express, and Wells Fargo — are still down this year. But its Apple and Amazon gains show the boss hasn't entirely lost his touch.