Breaking down the stocks Mark Massey and Scott Bradford (AltaRock Partners) bought, sold, and held in Q2 2025, including their holdings at the end of the quarter. All data sourced from AltaRock Partners' 13F filed on August 14, 2025.
Who is AltaRock Partners?
AltaRock Partners is a highly concentrated investment firm founded by Mark Massey and Scott Bradford, both Harvard MBA graduates with distinguished investment backgrounds. Massey previously worked at Seth Klarman's Baupost Group, while Bradford gained experience at Fiduciary Management Associates. The firm maintains an extremely focused portfolio typically comprising fewer than ten holdings with a combined value of approximately $4.8 billion. AltaRock's investment philosophy centers on identifying exceptional businesses with durable competitive advantages and holding them for the long term.
Altarockpartners.com
Q2 '25 13F filed with SEC
Portfolio Changes in Q2 2025
New positions
AltaRock Partners did not initiate any new positions during Q2 2025.
Bought
AltaRock Partners significantly increased their holdings in Amazon (AMZN) by over 1 million shares and more than doubled their position in Hilton (HLT) by adding approximately 271,000 shares, while making a minor addition to their Moody's (MCO) stake.
Sold
AltaRock Partners substantially reduced their Alphabet (GOOGL) position by approximately 2.4 million shares (a 70% reduction) and trimmed their Visa (V) holdings by 315,000 shares (a 37% reduction).
Holdings at the end of Q2 2025
| Ticker | Company | Weight | Change | Value |
|---|---|---|---|---|
| TDG | TransDigm | 27.2% | $1.49B | |
| AMZN | Amazon | 25.1% | Added (+21%) | $1.38B |
| MSFT | Microsoft | 23.4% | $1.28B | |
| MCO | Moody's | 8.7% | Added (+0%) | $477.64M |
| MA | Mastercard | 6.0% | $329.44M | |
| V | Visa | 3.5% | Trimmed (-37%) | $190.1M |
| GOOGL | Alphabet | 3.4% | Trimmed (-70%) | $184.24M |
| HLT | Hilton | 2.6% | Added (+99%) | $145.05M |
| FICO | Fair Isaac | 0.0% | $1.22M |
Disclaimer: All posts are for informational purposes only. They are NOT a recommendation to buy or sell the securities discussed. Please do your own research and due diligence before investing your money.
