The curated database of hedge funds that publish investor letters. Research by geography, strategy, and schools of thought.
| # | Fund | Strategy | Style | Geography | AUM | Latest Letter |
|---|---|---|---|---|---|---|
As of Dec 31, 2025
In his 2025 annual letter, Guy Spier announces the difficult decision to close the Aquamarine Fund to external investors and return approximately $235 million (about 50% of the fund's $470 million AUM). The decision follows a diagnosis and recurrence of grade 4 glioblastoma (GBM). Spier reports that in 2025, the fund returned 11.3% compared to 17.9% for the S&P 500. He outlines the orderly liquidation process, shares personal reflections on his 28-year investing career, and offers a five-point framework for selecting investment stewards (skin in the game, sole focus, run as an activity rather than a business, competence/candor, and the fiduciary gene). Going forward, the fund will transition to a family office, concentrating strictly on durable compounders like Berkshire Hathaway, Nestlé, and Mastercard.
True compounding success comes from selecting durable, time-friendly businesses managed by leaders with skin in the game, absolute focus, and a strong fiduciary gene, while systematically avoiding cyclical and binary-outcome risks.
The manager is winding down external capital and moving the remaining portfolio toward a low-maintenance, long-term approach focused on inevitable, durable compounders. This style allows him to devote more of his time and focus to his health and family, while still running the family office portfolio.
High Conviction Bullish
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Language Signal
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