Guy Spier's portfolio
Aquamarine Capital · SEC CIK 1953324
Buy great businesses, hold forever, stay off the treadmill.
This filing is 94 days old. Aquamarine Capital keeps roughly 89% of its positions in a typical quarter, so about 89% of this book is likely still intact today.
How half-life is computedSnapshot half-life is the number of days after the period end at which half of this specific fund's reported book is expected to have changed, measured from its own past filings. It is a decay estimate, not knowledge of current positions.
Largest holdings, as filed
Top 7 of 7 positions. Weights are against the whole filed book. 13F filings cover US-listed holdings only.
| Company | Ticker | Value | % of book | Freshness |
|---|---|---|---|---|
| BERKSHIRE HATHAWAY INC DEL | BRK/B | $48.84M | 33.9% | |
| BERKSHIRE HATHAWAY INC DEL | BRK/A | $22.47M | 15.6% | |
| AMERICAN EXPRESS CO | AXP | $21.99M | 15.3% | |
| MASTERCARD INCORPORATED | MA | $20.54M | 14.3% | |
| MOODYS CORP | MCO | $12.23M | 8.5% | |
| FERRARI N V | $11.11M | 7.7% | n/a | |
| DAILY JOURNAL CORP | DJCO | $6.91M | 4.8% |
Freshness: how likely each position is still held today, from this fund's own turnover history, each position's tenure and the filing's age. Hover a bar for the numbers. Method.
Common questions
What are Guy Spier's biggest holdings?
As of the Q2 2026 13F, the largest reported positions at Aquamarine Capital are BRK/B (33.9% of the book), BRK/A (15.6% of the book), AXP (15.3% of the book).
How big is Aquamarine Capital's portfolio?
The latest 13F reports $144.09M across 7 US-listed positions. 13F filings cover US-listed holdings only, so non-US positions and shorts are not included.
Does Guy Spier still hold these positions?
Unknown for certain: a 13F may be filed up to 45 days after quarter end. Based on Aquamarine Capital's own filing history, the fund keeps roughly 89% of positions in a typical quarter, so at 94 days since the period end roughly 89% of this book is likely intact. The snapshot half-life for this fund is about 554 days.
Funds with overlapping books
Every 13F we hold, quarter by quarter
Each filing has its own page: the whole book as filed that quarter and what changed from the filing before.
Inside the app: the full book for Aquamarine Capital, quarter on quarter buys and sells, consensus across 140+ funds and copy-to-watchlist.
Source: SEC EDGAR 13F filings. Values are as filed and cover US-listed positions only. A 13F may be filed up to 45 days after the quarter ends, so positions can change before the filing is even public; the freshness figures above quantify that lag instead of hiding it. Educational information, not financial advice.