Guy Spier - Aquamarine Capital Portfolio Q2'2025: Top Holdings & Recent Changes
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Guy Spier, the thoughtful value investor behind Aquamarine Capital, continues to exemplify patience and discipline in a market often driven by short-term noise. His Q2’2025 portfolio stands as a testament to long-term conviction, with $309.8 million allocated across 14 positions and virtually no turnover—a rarity among professional investors.
Portfolio Overview: The Power of Patience and Focus
Portfolio Highlights (Q2’2025): - Market Value: $309.8M - Top 10 Holdings: 98.1% - Portfolio Size: 14 +0 - Average Holding Period: 10 quarters - Turnover: 0.0%
The Aquamarine Capital portfolio remains a model of concentration and low activity, with the top 10 holdings representing a staggering 98.1% of total assets. This ultra-focused approach is a hallmark of Guy Spier’s strategy, reflecting deep conviction in a select group of businesses and a willingness to let investments compound over time. The portfolio size remains unchanged at 14 positions, and the average holding period of 10 quarters underscores a commitment to long-term ownership.
Notably, the portfolio’s 0.0% turnover this quarter signals a deliberate avoidance of market timing or reactionary trading. Spier’s approach is rooted in the belief that true value is realized over years, not months, and that minimizing activity can be a source of outperformance by reducing frictional costs and behavioral errors.
Top Holdings Analysis: Enduring Compounders and a Singular New Addition
The portfolio is anchored by a core group of financial and consumer franchises. Berkshire Hathaway is the largest position at 22.0%, unchanged this quarter, reflecting Spier’s admiration for Buffett’s conglomerate model. American Express follows closely at 21.6%, also with no change, highlighting a long-standing conviction in the power of brand and network effects in payments.
Mastercard 11.9% and Bank of America 11.7% round out the top four, both held steady, reinforcing the portfolio’s tilt toward financials with robust competitive advantages. Ferrari 8.1% and Micron Technology 8.0% add a blend of luxury and technology exposure, each representing significant long-term bets with no recent changes.
A notable feature is the dual listing of Berkshire Hathaway in both the second and eighth positions, likely reflecting different share classes or reporting nuances, together comprising nearly 29% of assets. Moody’s 4.4% and Alibaba 1.7% provide additional diversification into ratings and Chinese e-commerce, respectively.
The only portfolio action this quarter was an addition: Core Natural Resources saw a 32.59% increase, now at 0.2% of the portfolio. While small in size, this move suggests a selective willingness to add to positions where Spier sees asymmetric upside.
What the Portfolio Reveals About Current Strategy
- Quality Over Quantity: The overwhelming concentration in a handful of world-class businesses signals a relentless focus on quality and competitive moats.
- Financials and Payments Core: With outsized allocations to Berkshire Hathaway, American Express, Mastercard, and Bank of America, the portfolio is positioned to benefit from secular trends in finance and payments.
- Global Diversification: Holdings like Ferrari, Alibaba, and Micron Technology provide exposure to global growth and innovation.
- Minimal Activity, Maximum Patience: The 0.0% turnover and 10-quarter average holding period reflect a strategy built on patience, compounding, and the avoidance of unnecessary trades.
- Selective Opportunism: The only change—a meaningful add to Core Natural Resources—shows that Spier is willing to act decisively when the risk/reward skews in his favor.
Portfolio Concentration Analysis
| Position | Value | % of Portfolio | Recent Change |
|---|---|---|---|
| BERKSHIRE HATHAWAY INC DEL | $68.3M | 22.0% | No change |
| AMERICAN EXPRESS CO | $67.0M | 21.6% | No change |
| MASTERCARD INCORPORATED | $36.9M | 11.9% | No change |
| BANK AMERICA CORP | $36.3M | 11.7% | No change |
| FERRARI N V | $25.0M | 8.1% | No change |
| MICRON TECHNOLOGY INC | $24.7M | 8.0% | No change |
| BERKSHIRE HATHAWAY INC DEL | $21.9M | 7.1% | No change |
| MOODYS CORP | $13.5M | 4.4% | No change |
| ALIBABA GROUP HLDG LTD | $5.4M | 1.7% | No change |
The table above illustrates just how concentrated the Aquamarine Capital portfolio is, with the top four positions alone accounting for over 67% of assets. This level of focus is rare among professional managers and reflects a willingness to let the best ideas drive returns. The absence of significant changes across the top holdings further underscores Spier’s commitment to letting compounding work over time.
Investment Lessons from Guy Spier’s Value Discipline
- Concentrate When You Know: Spier’s willingness to allocate heavily to his highest-conviction ideas is a reminder that true outperformance often comes from focus, not diversification for its own sake.
- Hold for the Long Term: With an average holding period of 10 quarters and minimal turnover, Spier demonstrates that patience is a competitive advantage.
- Quality Businesses Endure: The portfolio’s core is built around companies with durable competitive advantages, strong brands, and proven management.
- Selective Action Beats Constant Activity: The only portfolio change was a targeted add to a small position, showing that activity should be driven by opportunity, not obligation.
- Risk Management Through Understanding: Deep research and conviction in each holding allow for concentration without undue risk.
Looking Ahead: What Comes Next?
With virtually no turnover and a stable roster of high-quality holdings, Aquamarine Capital is positioned to benefit from the continued compounding of its core positions. The selective add to Core Natural Resources hints at ongoing research into new opportunities, but the overall message is clear: Spier is content to let his winners run. Investors should watch for any future shifts in the portfolio, particularly if market volatility creates new bargains for this patient capital allocator.
FAQ about Guy Spier’s Aquamarine Capital Portfolio
Q: Why was there so little activity in the Q2 2025 portfolio?
Guy Spier’s approach emphasizes long-term compounding and only acts when there is a clear value opportunity. The 0.0% turnover this quarter reflects high conviction in existing holdings and a belief that inactivity can be a source of outperformance.
Q: How concentrated is the portfolio, and is this risky?
The portfolio is extremely concentrated, with the top 10 holdings making up 98.1% of assets. While this increases exposure to individual company risk, Spier mitigates this by focusing on businesses with strong competitive advantages and deep research.
Q: What is the average holding period, and why does it matter?
The average holding period is 10 quarters, underscoring a commitment to long-term investing. This allows for the benefits of compounding and reduces the impact of short-term market fluctuations.
Q: Which sectors or themes dominate the portfolio?
Financials and payments are the largest themes, with significant positions in Berkshire Hathaway, American Express, Mastercard, and Bank of America. There is also exposure to technology, luxury, and global growth through other holdings.
Q: How can I track Guy Spier’s portfolio in real time?
You can follow Aquamarine Capital’s latest 13F filings and portfolio changes on ValueSense. Keep in mind that 13F filings are reported with a 45-day lag, so there may be a delay between actual trades and public disclosure.
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