Billionaire Ken Griffin went on a shopping spree in the third quarter of 2025. His Citadel Advisors hedge fund bought a large number of stocks. In many cases, the transactions involved the purchase of millions of shares.
It probably shouldn't be surprising that Griffin owns all of the so-called "Magnificent Seven" stocks. After all, each member of the group ranks among the top 10 largest stocks in the world based on market cap. Griffin loaded up on every Magnificent Seven stock in Q3 – with one notable exception.
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Magnificent buys
Microsoft (MSFT 2.50%) is Citadel's largest holding. That wasn't the case earlier this year. However, Griffin doubled his hedge fund's position in Microsoft during Q3, buying roughly 2 million additional shares.
That purchase left Nvidia (NVDA 1.03%) in second place. Griffin bought 1.73 million more shares of the GPU maker last quarter, increasing Citadel's stake by 21.4%
One of the billionaire's biggest moves in Q3 involved Meta Platforms (META 1.16%). Griffin increased Citadel's position in the parent company of Facebook and Instagram by a whopping 12,693%. Meta is now the hedge fund's third-largest holding.
Another Magnificent Seven stock comes in fourth. Griffin more than doubled Citadel's stake in Apple (AAPL 0.68%) in Q3.
Additionally, Griffin picked up more shares of two other Magnificent Seven stocks in Q3 that aren't in his hedge fund's top 10 holdings. He bought another 1.1 million shares of Tesla (TSLA +4.17%) and another 1.25 million shares of Google parent Alphabet (GOOG +1.44%) (GOOGL +1.21%).
One glaring exception
That leaves one member of the elite group of stocks that Griffin no longer views as so magnificent. He sold 2.1 million shares of Amazon (AMZN 0.87%) in Q3, reducing Citadel's stake in the e-commerce and cloud services giant by 39%.
The obvious question is: Why did Griffin sour on Amazon? However, there isn't an obvious answer.
Amazon's AWS cloud unit benefits from the same artificial intelligence (AI) tailwinds as fellow cloud providers Microsoft and Alphabet's Google Cloud. Although AWS isn't growing as fast on a percentage basis as its rivals, it's still a strong business.
Griffin didn't sell Amazon in Q3 because the stock had become too expensive. Amazon's share price fell during part of the quarter, with its decline roughly in line with the moves of several other Magnificent Seven stocks.
NASDAQ: AMZN
Key Data Points
Amazon's quarterly update announced during Q3 didn't disappoint investors either. The company handily beat Wall Street's earnings estimate.
Perhaps the best explanation for Griffin's sale of the stock is that he was simply rebalancing Citadel's portfolio. The hedge fund has owned Amazon for years, frequently buying and selling shares with no apparent rhyme or reason.
Should you sell Amazon stock, too?
If we knew exactly why Griffin sold Amazon stock and agreed with the reasoning, following in his footsteps by selling the stock too would make sense. However, that's not the case here.
Even though Amazon reigns as the largest e-commerce company in the world, it still has plenty of room to grow in this market. As CEO Andy Jassy pointed out last year, Amazon's market share of the total global retail market is only around 1%.
Advertising is a key growth driver for Amazon these days. Revenue from advertising services jumped 24% year-over-year in Q3, a faster growth rate than AWS delivered.
Speaking of AWS, the cloud unit continues to have tremendous opportunities. Jassy spoke extensively about the promise of agentic AI during Amazon's latest quarterly earnings call. He noted, "AWS is heavily investing in this area and well-positioned to be a leader." I agree with him that agentic AI should serve as a significant tailwind for AWS.
Don't overlook Amazon's expansion into new markets, though. The company will begin offering satellite internet services in early 2026. Its Zoox robotaxis are now operating in Las Vegas, with Washington, D.C. on the way.
Griffin may or may not like Amazon as much now as he did earlier in the year. However, I think this stock remains a magnificent pick for long-term investors.
