Billionaire Bill Ackman Just Sold This Hot Artificial Intelligence Stock. Here's Why Wall Street Thinks He Made a Big Mistake.

Bill Ackman's Pershing Square trimmed its Alphabet Class A position by roughly 519,000 shares (about 9.7%) in Q3 2025 — part of a quarter in which Ackman opened no new positions, lightly cut Uber and reduced stakes in four holdings overall — while still holding over 11 million Alphabet shares valued at about $3.3 billion. Wall Street remains overwhelmingly bullish (an S&P Global survey of 66 analysts showed zero sell ratings, 12 strong buys and 45 buys), and Alphabet's strong Q3 results (revenue $102.3bn, +16% YoY; earnings ~$35bn, +33%) plus AI momentum — Google Gemini >650m MAUs, Gemini 3.0, accelerating Google Cloud, Waymo expansion and progress at Google Quantum AI — underpin the growth case. The trim looks like tactical profit-taking rather than a change in conviction, but it underscores active risk management amid a still-favorable, AI-driven long-term outlook for the company.

Analysis

Pershing Square reduced its Alphabet Class A stake by roughly 519,000 shares (about 9.7%) in Q3 2025 while opening no new positions and trimming stakes in four holdings; the fund still holds over 11 million Class A and B shares valued at approximately $3.3 billion. The move appears tactical given Pershing Square's concentrated 11-stock portfolio and the absence of public commentary explaining the sale.

Wall Street remains overwhelmingly bullish: an S&P Global survey of 66 analysts showed zero sell ratings, 12 strong buys, 45 buys and nine holds. Alphabet reported Q3 revenue of $102.3 billion (up 16% YoY) and earnings of roughly $35 billion (up 33%), supporting the positive analyst consensus.

Alphabet's AI momentum underpins the growth case: Google Gemini exceeds 650 million monthly active users, Gemini 3.0 has launched, Google Cloud growth is accelerating, Waymo plans expansion to 11 additional U.S. cities plus London, and Google Quantum AI has reported milestone progress. Ackman's trim looks like profit-taking rather than a change in conviction, but investors should monitor cloud adoption, Gemini/user engagement, Waymo rollout and future earnings cadence as execution risk factors.

Key Decisions for Investors

• Consider maintaining or modestly increasing exposure to Alphabet for long-term-oriented portfolios given robust Q3 results and AI-driven growth vectors,
• Treat Pershing Square's ~9.7% trim as tactical profit-taking rather than a sell signal; use the event to rebalance position sizing or take selective profits if your weighting is concentrated,
• Monitor near-term KPIs — Google Cloud growth rates, Gemini adoption metrics, Waymo expansion timelines and upcoming earnings — and implement size limits or hedges if these execution indicators weaken