AltaRock Partners Portfolio - Sep 30, 2025
AltaRock Partners, Mark Massey, has built a diversified portfolio of 9 publicly traded holdings with a total market value of $5.5B as of Sep 30, 2025. This comprehensive analysis examines the latest 13F filing data to understand the investment strategy and recent portfolio adjustments.
The portfolio demonstrates a concentrated approach to stock selection, with the top holding representing 30.3% of the total portfolio value. The top 5 holdings account for 92.5% of the overall portfolio allocation.
Recent portfolio activity shows 10 significant position adjustments, indicating active portfolio management and strategic repositioning. These changes reflect the investor's response to market conditions and evolving investment thesis.
Portfolio Statistics
Top Holdings Analysis
The portfolio's top holdings reveal the investor's core investment thesis and sector preferences. The largest position in AMAZON.COM INC (AMZN) represents 30.3% of the total portfolio, valued at $1.7B.
| Rank | Symbol | Company | Value | Portfolio % | Change |
|---|---|---|---|---|---|
| 1 | AMZN | AMAZON.COM INC | $1.7B | 30.3% | +20.4% |
| 2 | MSFT | MICROSOFT CORP | $1.3B | 24.3% | -0.4% |
| 3 | TDG | TRANSDIGM GROUP INC | $1.3B | 23.5% | -0.4% |
| 4 | MCO | MOODYS CORP | $452.1M | 8.3% | -0.4% |
| 5 | MA | MASTERCARD INC-CLASS A | $332.2M | 6.1% | -0.4% |
For a complete analysis of all holdings and detailed portfolio breakdown by sector and market cap, visit our comprehensive holdings page.
Recent Portfolio Activity
Recent portfolio adjustments provide insights into the investor's evolving strategy and market outlook.
The following table shows the top 10 most significant position changes from recent reporting periods (out of 159 total transactions), sorted by the magnitude of change.
For a complete history of all portfolio transactions and detailed activity analysis,
visit our comprehensive activity page.
| Symbol | Company | Quantity Change | Date | Action |
|---|---|---|---|---|
| AMZN | Amazon.com, Inc. | +1,282,347 | Sep 30, 2025 | BUY |
| GOOGL | Alphabet Inc. | -701,038 | Sep 30, 2025 | SELL |
| MSFT | Microsoft Corporation | -9,382 | Sep 30, 2025 | SELL |
| TDG | Transdigm Group Incorporated | -3,558 | Sep 30, 2025 | SELL |
| MCO | Moody's Corporation | -3,519 | Sep 30, 2025 | SELL |
| MA | Mastercard Incorporated | -2,168 | Sep 30, 2025 | SELL |
| HLT | Hilton Worldwide Holdings Inc. | -1,983 | Sep 30, 2025 | SELL |
| V | Visa Inc. | -1,890 | Sep 30, 2025 | SELL |
| FICO | Fair Isaac Corporation | -3 | Sep 30, 2025 | SELL |
| GOOGL | Alphabet Inc. | -2,408,938 | Jun 30, 2025 | SELL |
Investment Strategy Insights
AltaRock Partners's investment approach can be analyzed through several key metrics. The portfolio's concentration in top holdings suggests a high-conviction investment strategy, with significant positions in companies that align with the investor's long-term thesis.
The largest position in AMAZON.COM INC (AMZN) demonstrates strong conviction in this particular investment opportunity. Recent activity shows a increase of 20.4% in this position, indicating active portfolio management and strategic positioning.
Portfolio turnover can be assessed through recent activity patterns. The 10 most significant transactions shown here (out of 159 total transactions) suggest a highly active approach to portfolio management, with frequent strategic adjustments and position changes.
Additional Analysis
Complete Holdings
View all 9 holdings with detailed analysis
Trading Activity
Track all portfolio transactions and position changes
Performance Metrics
Analyze profit, winning trades, and investment returns
Sector Allocation
Analyze portfolio breakdown by sector and industry
AltaRock Partners's portfolio as of Sep 30, 2025 reflects a strategic approach to equity investing with 9 holdings valued at $5.5B. The concentrated position in AMAZON.COM INC and other top holdings demonstrates the investor's confidence in specific investment themes and long-term value creation opportunities. Recent activity indicates ongoing portfolio optimization and strategic repositioning.
For the most current portfolio data and detailed analysis, refer to the latest SEC 13F filings and our comprehensive holdings and activity pages, which are updated regularly with the latest filing information.
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