Breaking down the stocks Guy Spier (Aquamarine) bought, sold, and held in Q1 2025, including their holdings at the end of the quarter. All data sourced from Aquamarine's 13F filed on April 11, 2025.
Who are Guy Spier and Aquamarine Capital?
Guy Spier is the founder and portfolio manager of Aquamarine Fund (commonly referred to as Aquamarine Capital). The fund is known for its highly concentrated portfolio, typically consisting of 10-15 stocks, with the top 7 holdings comprising approximately 75% of assets, and cash holdings averaging around 5-6% when attractive opportunities are limited. His investment strategy is a global value investing approach inspired by Warren Buffett's original 1950s partnerships, emphasizing long-term compounding of intrinsic value and capital preservation while avoiding leverage and excessive trading. Spier focuses on undervalued, high-quality companies that occupy the "economic high ground," with strong qualitative factors like economic moats, high returns on invested capital, share repurchase programs, resilient brands, ecosystem control, and the ability to endure and compound sustainably over decades, often in sectors like financial services, luxury goods, and emerging market infrastructure.
Guyspier.com
Aquamarinefund.com
Guy Spier on X
Q1 '25 13F filed with SEC
Holdings in Q1 2025
| Ticker | Company | Weight | Change | Value |
|---|---|---|---|---|
| BRK-B | Berkshire Hathaway | 25.5% | $74.88M | |
| AXP | American Express | 19.2% | $56.5M | |
| MA | Mastercard | 12.3% | $36.04M | |
| BAC | Bank of America | 10.9% | $32.04M | |
| BRK-A | Berkshire Hathaway | 8.2% | $23.95M | |
| RACE | Ferrari | 8.0% | $23.53M | |
| MU | Micron | 5.9% | $17.38M | |
| MCO | Moody's | 4.3% | $12.57M | |
| BABA | Alibaba | 2.1% | $6.28M | |
| DJCO | Daily Journal | 1.6% | $4.57M | |
| GOOGL | Alphabet | 0.8% | $2.47M | |
| SRG | Seritage Growth Properties | 0.5% | $1.61M | |
| AMR | Alpha Metallurgical | 0.3% | $1M | |
| CNR | Core Natural Resources | 0.3% | NEW | $828K |
| ARCH | Arch Resources | 0.0% | Exited | $-1.14M |
Current Investment Strategy
Guy Spier's Aquamarine Capital maintained its concentrated value investing approach in Q1 2025, anchoring the portfolio in high-quality financial services franchises including Berkshire Hathaway, American Express, Mastercard, and Bank of America, alongside luxury brand Ferrari and credit rater Moody's. The Zurich-based investor rotated out of coal producer Arch Resources and into its newly-formed merger successor Core Natural Resources, while maintaining long-term positions in technology play Micron, China's e-commerce giant Alibaba, and Charlie Munger-linked Daily Journal.
New Investments
Core Natural Resources CNR
Guy Spier bought $828K of Core Natural Resources in Q1 2025. Core Natural Resources recovered sharply in Q3 2025, posting $0.61 earnings per share versus a -$0.70 loss in Q2, though performance remains below the $3.22 EPS from a year prior. The company generated $1.002 billion in revenue and $141.2 million in adjusted EBITDA, with strong free cash flow of $38.9 million fueling an aggressive capital return program. Despite improving operational fundamentals and expanding contracted sales positions, the stock declined 27.2% year-to-date compared to the S&P 500's 15.6% gain.
- EPS surged to $0.61 in Q3 from -$0.70 in Q2, representing a 143.57% earnings surprise versus consensus estimates.
- Generated $38.9 million in free cash flow while returning approximately 100% of year-to-date FCF to shareholders through $218.3 million in capital returns.
- Adjusted EBITDA reached $141.2 million in Q3; West Elk transition to higher-quality B-Seam expected to drive further margin improvements in coming quarters.
Added, Trimmed, and Exited
Added
Guy Spier did not add to any existing positions during Q1 2025.
Trimmed
Aquamarine did not trim any existing positions during Q1 2025.
Exited
Guy Spier fully liquidated his position in Arch Resources (ARCH), selling 8,100 shares valued at $1.144 million.
What it means: This exit appears to be a strategic sector rotation rather than an abandonment of the natural resources thesis. Spier simultaneously replaced Arch Resources with Core Natural Resources (CNR), investing $828K in the new position—notably less capital than the $1.144M liquidated from ARCH. This swap within the same industry suggests Spier may have identified more compelling value or operational fundamentals at Core Natural Resources, which despite a 27% year-to-date decline has demonstrated impressive earnings recovery (swinging from -$0.70 to $0.61 EPS quarter-over-quarter) and an aggressive shareholder return program that has returned approximately 100% of free cash flow. The partial redeployment of capital indicates measured conviction—Spier appears to be maintaining reduced exposure to the coal/natural resources sector while potentially banking some gains or managing concentration risk from the ARCH position.
Disclaimer: All posts are for informational purposes only. They are NOT a recommendation to buy or sell the securities discussed. Please do your own research and due diligence before investing your money.
