Warren Buffett Just Tripled Down on the Stock Bill Ackman Is Selling

Berkshire Hathaway (NYSE:BRK.B | BRK.B Price Prediction), now run by CEO Greg Abel with Warren Buffett serving as chairman, disclosed in Q1 2026 13F filings that it nearly tripled its Alphabet stake to roughly 57.8 million shares worth about $16.6 billion, vaulting Alphabet (NASDAQ:GOOGL) into a top-five Berkshire holding.

In the same window, Bill Ackman’s Pershing Square reportedly liquidated more than 95% of its Alphabet position and reallocated into Microsoft. Ray Dalio’s Bridgewater bought heavily on the same side as Berkshire, and Trump and Pelosi disclosed early-2026 buys of Alphabet as well. The smart money split itself in half over the same stock.

Why Berkshire tripled down on Alphabet

The case Abel’s team appears to be underwriting is straightforward, which is partly why it feels so Buffett-shaped. Alphabet’s Q1 2026 results showed EPS of $5.11 versus a $2.63 consensus, revenue of $109.90 billion, up 21.8% year over year, and Google Cloud growth of 63% with backlog nearly doubling quarter over quarter to over $460 billion. That backlog is the number that matters. It is contracted future demand, not a projection, and it dwarfs anything Alphabet has previously reported.

Valuation is the other half. Alphabet trades at a trailing P/E of 28x and a forward P/E of 25x, with an analyst target of $417. Sundar Pichai’s framing was characteristically measured: “Our AI investments and full stack approach are lighting up every part of the business.” Shares are up 115% over the past year and 15% year to date, but down 6% over the past month. Berkshire bought a compounder, on a pullback, at a multiple cheaper than the S&P average. That is the Buffett playbook even when Buffett isn’t pushing the buttons.

Ackman’s pivot to Microsoft

Ackman’s exit deserves to be read as a reallocation, not a thesis-breaking sell signal. He moved capital into Microsoft (NASDAQ:MSFT), where the AI numbers are arguably louder. Microsoft’s most recent quarter showed an AI business annual run rate of $37 billion, up 123% year over year, Azure growth of 40%, and commercial RPO of $627 billion, up 99%. The restructured OpenAI partnership leaves Microsoft with a roughly 27% stake worth approximately $135 billion and IP rights extended through 2032.

The trade is contrarian on price. Microsoft is down 20% year to date and 20.6% over the past year, trading around $378.9 against an analyst target of $565.9. Ackman is buying enterprise software lock-in at a forward P/E below 20x after a brutal drawdown. Different stock, similar instinct.

What retirement investors should take from the split

Both sides are betting on AI infrastructure. The disagreement is about who captures the economics. Berkshire’s wager is that Alphabet’s $175 to $185 billion of 2026 CapEx translates into durable cloud market share. This is at a price the market still treats as suspect. Ackman’s wager is that Microsoft’s enterprise distribution converts AI workloads to recurring revenue faster than anyone else.

The honest answer for a retirement-focused investor is that copying either trade without understanding the thesis is the wrong instinct. Following Berkshire into Alphabet makes sense if you believe cloud backlog is a real signal and the antitrust overhang is priced in. Following Ackman into Microsoft makes sense if you believe enterprise AI monetization has been temporarily mispriced. Both can be right. Owning a slice of each, sized to your time horizon, is closer to what the institutions are actually doing than picking a winner in someone else’s argument.