Guy Spier

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

Data as of 2026-06-30 (filed 2026-07-10) · Source: SEC EDGAR

Portfolio value$144.1M (+6%)

Holdings7

Top holdingBerkshire Hathaway Inc

Below band0

By what price implies: 4 demand a demanding growth rate, 0 modest.

13F · concentration

Lonely conviction

Held by ≤2 tracked superinvestors, each ≥3% of this portfolio (as of 2026-06-30):

Daily Journal CorpDJCO5% · 1

SEC 13F · latest filing

Holdings

Security	Value	Valuation	Holders	Shares	Weight	Signal
Berkshire Hathaway IncBRK.B	$48.8M	—	27	97,600	33.9%	Core 8q
Berkshire Hathaway IncBRK.A	$22.5M	—	17	30	15.6%	Core 8q
American Express CoAXP	$22.0M	—	16	65,000	15.3%	Core 8q
Mastercard IncorporatedMA	$20.5M	—	21	40,000	14.3%	Core 8q
Moodys CorpMCO	$12.2M	—	20	27,000	8.5%	Core 8q
Ferrari N VRACE	$11.1M	—	3	30,000	7.7%	—
Daily Journal CorpDJCO	$6.9M	—	1	11,500	4.8%	No trim 8q

Berkshire Hathaway IncBRK.BCore 8q
Value$48.8MValuation—Holders27Weight33.9%
Berkshire Hathaway IncBRK.ACore 8q
Value$22.5MValuation—Holders17Weight15.6%
American Express CoAXPCore 8q
Value$22.0MValuation—Holders16Weight15.3%
Mastercard IncorporatedMACore 8q
Value$20.5MValuation—Holders21Weight14.3%
Moodys CorpMCOCore 8q
Value$12.2MValuation—Holders20Weight8.5%
Ferrari N VRACE—
Value$11.1MValuation—Holders3Weight7.7%
Daily Journal CorpDJCONo trim 8q
Value$6.9MValuation—Holders1Weight4.8%

What is a superinvestor

About this investor

Portfolio overview

Aquamarine Zurich AG's most recent 13F filing, for the quarter ended 2026-06-30, reports 7 positions worth $144.1M. The top 5 holdings represent 87% of that value, a concentrated portfolio.

The single largest position is Berkshire Hathaway Inc at 33.9% of the portfolio, followed by Berkshire Hathaway Inc at 15.6% and American Express Co at 15.3%.

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.

Guy Spier has no positions in the strike zone right now. Browse the whole market by value band

Sources· SEC EDGAR 13F as of 2026-06-30 · filed 2026-07-10

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