Aquamarine Zurich AG

Fundamental concentrated ★Highest signal financials specialist (65%) CIK 1953324
League rank
#308
in Fundamental concentrated · #797 overall
Long book
$135.3M
Q1 2026
Positions
7
Top-10 weight
100%
concentration
Last quarter
+9.8%
SPY +14.8%
Turnover
0%
of book per quarter

Strategy in plain words

auto-generated from filings

Aquamarine Zurich AG is a concentrated fundamental stock-picker, specialised in financials (65% of the long book), running a $135.3M US long book across 7 positions.

The portfolio is extremely concentrated — the top 10 positions are almost the whole book. The book barely moves quarter to quarter — a patient, low-turnover holder. Current anchor positions: BERKSHIRE HATHAWAY INC-CL B, BERKSHIRE HATHAWAY INC-CL A, MASTERCARD INC - A, AMERICAN EXPRESS CO, MOODY'S CORP.

Over the last 9 quarters its long book ran on average 1pp per quarter behind the S&P 500, beating the index in 3 of 9 quarters. We rate its filings highest-signal: new buys here are worth attention.

Implied long-book return vs S&P 500

methodology: positions priced quarterly, no shorts/options
Fund long book S&P 500
Q1 2024
-0.8%
Q2 2024
+9.1%
Q3 2024
+1.1%
Q4 2024
+2.9%
Q1 2025
+6.5%
Q2 2025
+7.7%
Q3 2025
+4.5%
Q4 2025
-9.1%
Q1 2026
+9.8%

Sector allocation

Financials
65%
Services media
23%
Industrials
7%
Other
4%

Long book by quarter

$261.9M
Q1 2024
$262.6M
Q2 2024
$285.6M
Q3 2024
$287.6M
Q4 2024
$293.7M
Q1 2025
$309.8M
Q2 2025
$317.4M
Q3 2025
$147.5M
Q4 2025
$135.3M
Q1 2026

What does Aquamarine Zurich own?

Q1 2026 13F
CompanySectorSharesValue% of bookChange
BRK/B BERKSHIRE HATHAWAY INC-CL BFinancials97.6K$46.8M34.6%Held
BRK/A BERKSHIRE HATHAWAY INC-CL AFinancials30$21.5M15.9%Held
MA MASTERCARD INC - AServices media40.0K$20.0M14.8%Held
AXP AMERICAN EXPRESS COFinancials65.0K$19.7M14.5%Held
MCO MOODY'S CORPServices media27.0K$11.8M8.7%Held
RACE FERRARI NVIndustrials30.0K$10.0M7.4%Held
DJCO DAILY JOURNAL CORPOther11.5K$5.5M4.1%Held

13F filing history

PeriodFormFiledEntriesReported valueFlagsSource
Q1 202613F-HRApr 17, 20267$135.3M $K fixed canonicalSEC ↗
Q4 202513F-HRJan 15, 20267$147.5M $K fixed canonicalSEC ↗
Q3 202513F-HROct 20, 202514$317.4M $K fixed canonicalSEC ↗
Q2 202513F-HR/ARESTATEMENTJul 18, 202514$309.8M $K fixed canonicalSEC ↗
Q2 202513F-HRJul 16, 202514$310K SEC ↗
Q1 202513F-HR/ARESTATEMENTJul 18, 202514$293.7M $K fixed canonicalSEC ↗
Q1 202513F-HRApr 11, 202514$294K SEC ↗
Q4 202413F-HRJan 24, 202514$287.6M $K fixed canonicalSEC ↗
Q3 202413F-HROct 16, 202414$285.6M $K fixed canonicalSEC ↗
Q2 202413F-HRJul 11, 202414$262.6M $K fixed canonicalSEC ↗
Q1 202413F-HRApr 18, 202412$261.9M $K fixed canonicalSEC ↗