Warren Buffett's company Berkshire Hathaway recently filed its 13F form with the Securities and Exchange Commission (SEC), disclosing what stocks the large conglomerate held at the end of the second quarter. Using these filings, investors can see what stocks Berkshire bought and sold in a three-month window and get a rare glimpse into the minds of some of the smartest investors in the world.
Berkshire has been a bit muted in recent quarters, choosing to pile into cash. But the company did make some notable moves in the second quarter, selling one decent-sized position and loading up on an artificial intelligence (AI) infrastructure stock.
After a strong year, Berkshire calls it quits on T-Mobile
The one position that Berkshire completely exited in the quarter was in the large mobile carrier T-Mobile (TMUS 0.28%). The company sold its entire position that had been valued at over $1 billion. Based on filings, Berkshire initiated its position in T-Mobile toward the end of 2020, and appears to have done well on the stock, which is up over 120% in the past five years.
Image source: The Motley Fool.
T-Mobile has also had a strong 2025, with the stock up about 16.5% (as of Aug. 15), and it recently reported strong second-quarter earnings. Diluted earnings per share of $2.84 rose about 14% year over year, while revenue jumped nearly 7%. Meanwhile, the company achieved some of its best-ever customer growth in the quarter, including 12% growth in its 5G broadband customer base, which is among the best in the industry.
In 2023, T-Mobile initiated a dividend, which it has already grown significantly, and management's goal is to grow the quarterly dividend 10% annually. The team at Berkshire may simply be choosing to sell T-Mobile high. The stock is not far off from all-time highs and is now trading at a fairly high forward price-to-earnings ratio above 23. That's toward the higher end of where it has historically traded in recent years, and well above peers. The company has earned the valuation but Berkshire may see it as fairly priced right now.
Berkshire has been secretly buying this AI infrastructure stock
Many investors came into this 13F season excited about Berkshire once they realized that it would unveil some mystery stocks. Funds can request permission from the SEC to keep certain positions confidential for a certain amount of time. So Berkshire actually purchased Nucor (NUE -0.49%) in the first quarter, but the market only just found out about it in the company's second-quarter 13F. Berkshire's position in Nucor amounted to over $850 million at the end of the second quarter.
Nucor is a steel company at its core. However, AI investors have gotten very interested because Nucor makes steel parts for data centers, which are in high demand to power and store all of the necessary data for large language models and AI applications. As a result of this and the way Nucor is positioned to support other burgeoning sectors, the stock has ripped close to 215% over the past five years and is up about 27% this year.
Nucor's earnings through the first six months of the year are down significantly compared to last year, as the costs to make its steel products have risen. Investors were also disappointed by management's third-quarter guidance calling for "nominally lower" earnings, mainly due to margin compression in some of its segments.
But the market expects President Donald Trump's 50% steel tariffs to benefit U.S. steel companies like Nucor, which will have an easier time raising prices because steel manufactured in other countries will be less competitive and more expensive. However, it could take time for higher prices to roll through. Nucor trades at about 17.5 times forward earnings, which I wouldn't necessarily call cheap in the steel sector.
However, we have seen Buffett and his team get interested in U.S.-based commodity companies like oil and gas, perhaps due to a belief in increasing demand over time and a finite supply. Nucor could fit into this theme.
