Aquamarine Capital

Guy Spier

$144.1M Portfolio Value
7 Stocks
+2.14% YTD Return
Jul 10, 2026 Last Updated
Portfolio Value Over Time

Current Holdings for Aquamarine Capital

Stock Click to search
Shares Value % of Portfolio Change Est. Return
BRK-B|Berkshire Hathaway Inc
97.6K $48.8M
33.89%
BRK-A|Berkshire Hathaway Inc
30 $22.5M
15.59%
AXP|American Express Co
65.0K $22.0M
15.26%
MA|Mastercard Incorporated
40.0K $20.5M
14.26%
MCO|Moodys Corp
27.0K $12.2M
8.49%
RACE|Ferrari N V
30.0K $11.1M
7.71%
DJCO|Daily Journal Corp
11.5K $6.9M
4.80%

Trading Activity for Aquamarine Capital

Stock Click to search
Action Change Shares After Value Est. Return
2026-Q2
No position changes reported in this filing.
2026-Q1
No position changes reported in this filing.
2025-Q4
BRK-B|Berkshire Hathaway Inc
SELL -30.58% 97.6K $49M
AXP|American Express Co
SELL -69.05% 65.0K $24M
BAC|Bank America Corp
SELL EXIT
MA|Mastercard Incorporated
SELL -39.16% 40.0K $23M
RACE|Ferrari N V
SELL -50.00% 30.0K $10M
MU|Micron Technology Inc
SELL EXIT
BABA|Alibaba Group Hldg Ltd
SELL EXIT
GOOGL|Alphabet Inc
SELL EXIT
SRG|Seritage Growth Pptys
SELL EXIT
AMR|Alpha Metallurgical Resour I
SELL EXIT -45.6%
CNR|Core Natural Resources Inc
SELL EXIT +2.8%
2025-Q3
MU|Micron Technology Inc
SELL -60.00% 80.0K $13M
2025-Q2
No position changes reported in this filing.
2025-Q1
ARCH1USD|Arch Resources Inc
SELL EXIT
CNR|Core Natural Resources Inc
BUY NEW 10.7K $828000 +24.3%
2024-Q4
No position changes reported in this filing.
2024-Q3
No position changes reported in this filing.
2024-Q2
AMR|Alpha Metallurgical Resour I
BUY NEW 8.0K $2M -26.2%
ARCH1USD|Arch Resources Inc
BUY NEW 8.1K $1M
2024-Q1
RACE|Ferrari N V
SELL -25.00% 60.0K $26M
2023-Q4
No position changes reported in this filing.
2023-Q3
No position changes reported in this filing.
2023-Q2
No position changes reported in this filing.
2023-Q1
No position changes reported in this filing.
2022-Q4
No position changes reported in this filing.

Closed Positions for Aquamarine Capital

Stock Click to search
Held Period Cost Basis Sale Proceeds Realized Gain Return CAGR
AMR|Alpha Metallurgical Resour I
2024-Q2 → 2025-Q4 (1.5y) $2.5M $1.3M $-1.1M -45.6% -33.4%
CNR|Core Natural Resources Inc
2025-Q1 → 2025-Q4 (0.7y) $878.4K $902.6K $+24.2K +2.8% +3.7%