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Q2 2026 holdings · 8 filings on record

Aquamarine Zurich AG

Guy Spier

Aquamarine is the investment business of Guy Spier, a Zurich-based investor who has managed Aquamarine's privately offered funds since 1997. It began with capital from family and friends and later took in outside investors. Its philosophy was inspired by Warren Buffett's original partnerships of the 1950s: global, long-term and value-focused, with every investment decision made by Spier alone. Spier wrote The Education of a Value Investor, which tells how a charity lunch with Buffett, won with Mohnish Pabrai and held in 2008, changed his approach. The filer tracked here is Aquamarine Zurich AG, the Swiss adviser Spier leads as chief executive.

AI-written, awaiting an editor · as of Oct 31, 2026 · not from the filings · 5 sources
  1. Aquamarine: Overview aquamarinefund.com ↗
  2. Aquamarine: Guy Spier aquamarinefund.com ↗
  3. NBC News: Bid wins lunch with Buffett nbcnews.com ↗
  4. TIME: Guy Spier on his lunch with Warren Buffett time.com ↗
  5. SEC: Form ADV, Aquamarine Zurich AG reports.adviserinfo.sec.gov ↗
Held on Jun 30, now 124 days oldReported to the SEC Jul 10, 2026Next filing due Nov 16 · 15 days
US-listed stocks held$144.1M
Positions7
Behaves like5equal-sized positions
Top 10 holdings100.0%of the total

Holdings

On June 30, 2026, Aquamarine Zurich AG held 7 positions in US-listed stocks worth $144.1 million.

  1. 1BERKSHIRE HATHAWAY INC DELBRK.BCL B NEW$48.8M33.9%
  2. 2BERKSHIRE HATHAWAY INCBRK.ACL A$22.5M15.6%
  3. 3American Express CompanyAXP$22M15.3%
  4. 4Mastercard IncMACL A$20.5M14.3%
  5. 5MOODYS CORPMCO$12.2M8.5%
  6. 6Ferrari N.V.RACE$11.1M7.7%
  7. 7Daily Journal CorporationDJCO$6.9M4.8%

What this filing cannot show

A 13F is a partial picture. Here is the part that is missing.

It lists long positions in US-listed stocks and options only. Not short positions, cash, ordinary bonds, anything listed only abroad, anything private, or anything bought and sold inside the quarter.

What is a 13F?

A quarterly SEC filing where large investment managers list the long positions in US-listed stocks and options they held at the end of the quarter. It is a snapshot, filed up to 45 days after that date.

Why is this list weeks old?

Managers have 45 days after each quarter ends to file, and most of the funds we track file on the last permitted day. So the newest list still describes where the fund stood weeks ago, and the market has moved since.

What does “behaves like” mean?

How many equal-sized positions would be exactly this concentrated. Ten positions of the same size behave like 10. Ten positions where one holds most of the money behave like fewer than 2. It is 1 divided by the sum of each position’s squared share of the total.

Why are two lines sometimes the same company?

Each line is one security as the manager filed it. Two share classes of one company, or a company’s stock and its convertible notes, are separate lines in the filing, and they stay separate here.

Filing history

8 filings on record.

Quarter endedReported to the SECPositionsSource
Jun 30, 2026Jul 10, 20267Open the SEC filing ↗
Mar 31, 2026Apr 17, 20267Open the SEC filing ↗
Dec 31, 2025Jan 15, 20267Open the SEC filing ↗
Sep 30, 2025Oct 20, 202514Open the SEC filing ↗
Jun 30, 2025Jul 18, 202514Open the SEC filing ↗
Mar 31, 2025Amended Jul 18, 202514Open the SEC filing ↗
Dec 31, 2024Jan 24, 202514Open the SEC filing ↗
Sep 30, 2024Oct 16, 202414Open the SEC filing ↗

Where a manager later amended a filing, the date shown is the amendment’s. Every filing from this fund at the SEC ↗

⚠️ Public information, sourced from SEC 13F filings. A 13F shows long US-listed positions only; it cannot show shorts, cash, ordinary bonds, foreign lines, or anything bought and sold within the quarter. Values are the manager’s own quarter-end figures, filed up to 45 days later. Not financial advice.