Nobel Prize-winning theoretical physicist Richard Feynman once stated, "No one understands quantum mechanics." I mention Feynman's quote because many investors are excited about quantum computing stocks these days – and quantum computing is based on the principles of (you probably guessed it) quantum mechanics.
That leads me to another quote, in this case a statement made by Warren Buffett: "Never invest in a business you cannot understand." Buffett has also written about only investing in companies within your "circle of competence."
With all of this in mind, you might think that Buffett wouldn't touch a quantum computing stock with a 10-foot pole. However, $7.7 billion of his Berkshire Hathaway (BRK.A +0.59%) (BRK.B +1.12%) portfolio is invested in two quantum computing stocks.
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Buffett's two quantum computing stocks
Has Buffett quietly bought shares of D-Wave Quantum (QBTS +20.00%), IonQ (IONQ +10.90%), or Rigetti Computing (RGTI +12.84%)? Nope. I doubt that he'd give any of these up-and-coming quantum computing stocks a second of his attention. However, the legendary investor has acquired shares in two other companies that are investing heavily in quantum computing.
In 2019, Berkshire initiated a new position in Amazon (AMZN +0.47%). Buffett later acknowledged that one of the conglomerate's two investment managers decided to buy Amazon. But Buffett also admitted that he had been "an idiot" for not investing in the company earlier.

NASDAQ: AMZN
Key Data Points
Amazon is a bigger player in quantum computing than you might think. Amazon Web Services (AWS) offers Amazon Braket, a cloud service that allows researchers to test quantum computing algorithms, test quantum hardware, and develop quantum software. Amazon also introduced its Ocelot quantum computing chip earlier this year. Ocelet supports quantum error reduction by up to 90%.
Buffett has also expressed regret for not investing in Google's parent company, Alphabet (GOOG +0.88%) (GOOGL +0.86%), earlier. He corrected that mistake in 2025. Berkshire bought over 17.8 million shares of the tech giant.

NASDAQ: GOOGL
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Alphabet's Google Quantum AI is another pioneer in the field of quantum computing. In 2019, the unit developed a quantum system that performed a calculation in 200 seconds that it said "would have taken the best-known algorithms in the most powerful supercomputers at the time 10,000 years to accomplish." Google Quantum AI also demonstrated the first logical qubit prototype in 2023.
More than quantum computing
Today, Berkshire's stakes in these two quantum computing stocks amount to around $7.7 billion. However, Buffett and his team didn't buy shares of Amazon or Alphabet because of their quantum computing initiatives. I doubt that the companies' quantum computing efforts even factored into the investing decisions at all.
Amazon's dominance in e-commerce and cloud computing was a significant attraction for Berkshire when it first invested in the company in 2019. Over six years later, Amazon remains the No. 1 player in both markets.
Alphabet is, at its heart, an advertising company. Ads on Google Search, YouTube, the Google Network, and other apps generate roughly 72% of Alphabet's total revenue. While Buffett may not fully understand quantum computing and other advanced technologies, he certainly has a firm grasp of advertising.
Both Amazon and Alphabet offer more than their core businesses, though. For example, Amazon is preparing to launch a satellite internet service. Google Cloud is a key growth driver for Alphabet. Also, the company's famous "other bets" include self-driving car leader Waymo and high-speed internet provider GFiber.
Are Alphabet and Amazon good stocks to buy?
Don't buy Alphabet and Amazon just because Buffett owns the stocks. However, I think both are good picks for many investors.
Artificial intelligence (AI) presents a massive tailwind for AWS and Google Cloud. Amazon and Google should especially profit as the adoption of agentic AI grows. Both giants have significant opportunities in the robotaxi market.
Buffett's two quantum computing stocks are more than just investments in quantum computing. However, I think Alphabet and Amazon could be big winners as quantum computing advances – whether you understand the technology or not.











