Warren Buffett's Successor, Greg Abel, Is Betting Big on a Virtual Monopoly That's About to Become Berkshire Hathaway's 4th-Largest Holding

This year marks a new era for the trillion-dollar company that billionaire Warren Buffett built. The Oracle of Omaha retired as Berkshire Hathaway's (NYSE: BRKA)(NYSE: BRKB) CEO on Dec. 31, officially passing the torch to his protégé, Greg Abel.

Abel has wasted little time making his presence known. According to Berkshire's first-quarter Form 13F, he completely exited 16 positions and put tech stocks back on the menu, as evidenced by his sizable investment in Google parent Alphabet (NASDAQ: GOOGL)(NASDAQ: GOOG).

It took just one quarter for Abel to make clear that this isn't your grandparents' Berkshire Hathaway anymore -- and he's not done transforming Berkshire's $325 billion investment portfolio just yet.

Warren Buffett retired as Berkshire's CEO on Dec. 31, 2025. Image source: The Motley Fool.

Abel continues to pile into one of Wall Street's leading virtual monopolies

During the first quarter, Abel more than tripled Berkshire's stake in Alphabet's Class A shares (GOOGL) with a 36,403,656-share purchase, and opened a brand-new position in the Class C shares (GOOGL) with a 3,585,215-share purchase.

On June 1, Alphabet announced plans to sell $80 billion in stock to fund the expansion of its artificial intelligence (AI) infrastructure. Days later, it upsized its stock offering to a staggering $84.75 billion. Abel's Berkshire committed to buying $10 billion of this offering in a private placement ($5 billion Class A and $5 billion Class C). This additional investment will make Alphabet a top-four holding, with the market value of this position exceeding $30 billion.

Alphabet is dropping $80bn in equity to fund mass CapEx for AI compute dominance: $30bn public, $40bn ATM, and $10bn in a private placement with Berkshire.

Greg Abel isn't waiting. Buffett never embraced big tech, Abel is betting on it. pic.twitter.com/AU9lLxR3Bs

-- JUNK BOND ANALYST (@junkbondanalyst) June 1, 2026

Most investors are familiar with Alphabet's virtual monopoly status in internet search. Google has accounted for between 89% and 93% of global internet search traffic over the trailing decade, per GlobalStats. When coupled with Alphabet's ownership of YouTube, the second-most-visited social site on the planet behind Google, it's easy to see why it possesses truly exceptional ad-pricing power.

But there's much more to Berkshire's new No. 4 holding than just premium ad pricing power and strong cyclical ties. It's risen through the ranks to become a leading AI stock.

While Nvidia has established itself as the hardware kingpin of the AI revolution, Alphabet is making a strong case to be the premier deployer of AI applications. Since integrating generative AI solutions and large language model capabilities into Google Cloud, sales for Alphabet's cloud infrastructure services platform have soared. Revenue for the world's No. 3 cloud infrastructure services platform jumped 63% in the March-ended quarter compared with the previous year.

Although cutting-edge technology and large-scale tech companies were typically outside the scope of Warren Buffett's knowledge, this isn't the case with Berkshire's new boss. Abel recognizes Alphabet's sustainable moat in advertising, its key position in AI applications, and has likely been attracted by a valuation that, until recently, had been consistently cheaper on a forward-earnings basis than the benchmark S&P 500.

We may be witnessing the birth of a new multidecade/core holding for Abel and Berkshire Hathaway.

Sean Williams has positions in Alphabet. The Motley Fool has positions in and recommends Alphabet, Berkshire Hathaway, and Nvidia. The Motley Fool has a disclosure policy.