Gates Foundation Trust Rebuilt to $35.4B in Q4 2025 After a $8B Q3 — BRK/B Still Leads at 27.6%

TL;DR

• AUM: $35.4B across 23 holdings (Q4 2025)
• Top holding: Berkshire Hathaway (BRK/B) at 27.6% — $9.8B
• #2: Waste Management (WM) at 18.0% — $6.4B
• #3: Canadian National Railway (CNI) at 14.5% — $5.1B
• AUM recovery: $8.0B (Q3) → $35.4B (Q4), a +342% QoQ jump
• Holdings count: 9 (Q3) → 23 (Q4) — 14 positions added
• Top-5 concentration: 80.9%
• Theme: Infrastructure-heavy portfolio — waste, rail, industrial, software

The Foundation's Rebuilt Portfolio

Gates Foundation Trust manages the investment portfolio that funds the Bill & Melinda Gates Foundation. After a dramatic Q3 drop from $47.8B to just $8.0B (likely a large charitable distribution or reporting restructuring), the trust rebuilt to $35.4B across 23 positions in Q4 2025.

Berkshire Hathaway: The Anchor

Berkshire Hathaway (BRK/B) at $9.8B (27.6%, 19.4M shares) remains the foundation's largest holding — a position that dates back decades to the Gates-Buffett relationship. Even after years of gradual selling, Berkshire still anchors the portfolio.

Infrastructure and Compounders

Waste Management (WM) at $6.4B (18.0%) and Canadian National Railway (CNI) at $5.1B (14.5%) are the #2 and #3 positions. Both are infrastructure monopolies — the kind of durable, capital-light businesses Gates Foundation has favored.

Microsoft (MSFT) at $3.7B (10.5%) and Caterpillar (CAT) at $3.6B (10.3%) round out the top five. The Microsoft position is far smaller than it once was — the foundation has been steadily reducing its Microsoft exposure for years.

The Long Tail: Industrial Quality

Beyond the top 5, the portfolio includes Deere (DE), Ecolab (ECL), Walmart (WMT), FedEx (FDX), and Coca-Cola FEMSA (KOF). Every name in the portfolio has either pricing power, a regulatory moat, or both. There are zero speculative tech names.

The Q3 Anomaly

The Q3 2025 filing showed only $8.0B and 9 holdings — a drop from $47.8B and 25 holdings in Q2. The Q4 recovery to $35.4B and 23 holdings suggests this was a temporary reporting disruption rather than a permanent liquidation. The foundation may have restructured its trust vehicles or executed a large distribution that temporarily depleted the 13F-reporting entity.

What Analysts Might Misread

"Gates Foundation is buying aggressively again"

The $8B → $35.4B jump is almost certainly a reporting-entity normalization, not new capital deployment. The holdings mix is nearly identical to pre-Q3 quarters.

"Microsoft is no longer important to Gates"

At 10.5% ($3.7B), Microsoft is still the #4 holding. The gradual reduction reflects diversification, not abandonment.

Frequently Asked Questions

What stocks does the Gates Foundation own?

The Q4 2025 13F shows 23 positions led by Berkshire Hathaway (27.6%), Waste Management (18.0%), Canadian National Railway (14.5%), Microsoft (10.5%), and Caterpillar (10.3%).

Does the Gates Foundation still own Microsoft stock?

Yes, though the position has been reduced over the years. As of Q4 2025, the trust holds $3.7 billion in Microsoft shares, representing 10.5% of the portfolio.

Why did the Gates Foundation's AUM drop in Q3 2025?

The drop from $47.8B to $8.0B likely reflects a large charitable distribution or a restructuring of the trust's reporting entities, not a market loss.