One name, Mastercard Inc (MA), is 14.26% of what Guy Spier's Aquamarine Capital reports for 2026 Q2, according to the 13F-HR filed with the SEC on July 10, 2026. The stake is 40K shares worth about $20.5M, the 4th largest of 7 stock positions. Guy Spier left the share count unchanged from the prior quarter.
What did the 2026 Q2 filing report for MA?
As of June 30, 2026, from the 13F-HR filed July 10, 2026.
| Value | |
|---|---|
| Portfolio weight | 14.26% |
| Shares | 40K |
| Reported value | $20.5M |
| Rank in portfolio | 4th of 7 |
| Largest holding | BRK-B at 33.89% |
| Top three holdings | 64.74% of the book |
| Change this quarter | unchanged |
How concentrated is Guy Spier in MA?
MA at 14.26% is 1 times the average stock position in the Guy Spier portfolio, which is 14%. The largest holding is BRK-B at 33.89%. The three largest stocks together are 64.74% of the reported book. A quarter earlier MA was 14.77% of the book.
Where does MA sit in the Guy Spier portfolio?
MA ranks 4th of 7 stock positions in the Guy Spier portfolio at 14.26%, about the fund's average stock position of 14%. Across the 2026 Q2 portfolio, Guy Spier reported 7 stock positions, with no position opened or closed. The total portfolio value is about $144.1M, up 6% from the prior quarter.
How long has Guy Spier held MA?
Guy Spier first reported MA in the quarter ended December 31, 2014. The weight peaked at 15.48% in 2025 Q4. The share count was unchanged the quarter before. Every reported trade is on the Guy Spier MA trade history page.
Did other funds buy or sell MA in 2026 Q2?
Among the other tracked funds that had filed for 2026 Q2 as of July 10, 2026, 20 hold MA. Of those, 2 opened it this quarter. Another 2 sold out of it. The largest buyers of MA this quarter were Eagle Capital Management, Bill Ackman and Terry Smith. The largest sellers were Lewis Sanders, Chuck Akre and Thomas Russo. Every tracked holder of MA is on the MA ownership page.
FAQ
What share of the Guy Spier portfolio is MA?
MA is 14.26% of the Guy Spier portfolio as of 2026 Q2, the 4th largest of 7 stock positions.
What is the MA stake of Guy Spier worth?
Guy Spier holds 40K shares of MA, worth about $20.5M at June 30, 2026 prices, 14.26% of the reported portfolio.
What are the largest holdings of Guy Spier?
The largest stock positions of Guy Spier as of 2026 Q2 are BRK-B (33.89%), BRK-A (15.59%) and AXP (15.26%), together 64.74% of the book.
Did Guy Spier's Aquamarine Capital change its MA position in 2026 Q2?
Guy Spier left the share count unchanged from the prior quarter.