Compounder

Guy Spier

Aquamarine Zurich AG — managed by Guy Spier; US equity positions disclosed quarterly via SEC 13F

Data as of 2026-03-31 (filed 2026-04-17) · Source: SEC EDGAR

Portfolio value$135.3M8%)
Holdings7
Latest period2026-03-31
Top holdingBerkshire Hathaway Inc
Portfolio overview

Aquamarine Zurich AG's most recent 13F filing, for the quarter ended 2026-03-31, reports 7 positions worth $135.3M. The top 5 holdings represent 88% of that value, a concentrated portfolio.

The single largest position is Berkshire Hathaway Inc at 34.6% of the portfolio, followed by Berkshire Hathaway Inc at 15.9% and Mastercard Incorporated at 14.8%.

Against the prior quarter, Guy Spier opened 0 new positions, exited 0, added to 0, and trimmed 0.

Across all 8 quarters on file, Berkshire Hathaway Inc has appeared in every filing, as has Berkshire Hathaway Inc. Berkshire Hathaway Inc currently ranks first by value.

A 13F is filed roughly 45 days after quarter-end and covers only long positions in US-listed equities, so it is a lagging and partial view of the portfolio. Source: SEC EDGAR.

High-conviction
Holdings

Sources· SEC EDGAR 13F as of 2026-04-17

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