Mark Massey - AltaRock Partners Portfolio (Q1 2026)

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AltaRock Partners, Mark Massey, has built a diversified portfolio of 8 publicly traded holdings with a total market value of $4.1B as of Mar 31, 2026. 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 38.2% of the total portfolio value. The top 5 holdings account for 95.9% 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

8
Total Holdings
$4.1B
Portfolio Value
Mar 31, 2026
Latest Filing
38.2%
Largest Position

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 38.2% of the total portfolio, valued at $1.6B.

Rank Symbol Company Value Portfolio % Change
1 AMZN AMAZON.COM INC $1.6B 38.2% +3.5%
2 TDG TRANSDIGM GROUP INC $1.1B 25.5% -6.2%
3 MSFT MICROSOFT CORP $691.3M 16.8% -10.3%
4 MCO MOODYS CORP $376.1M 9.1% +5.8%
5 MA MASTERCARD INC-CLASS A $261.2M 6.3% -3.5%

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 165 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
HLT Hilton Worldwide Holdings Inc. -527,272 Mar 31, 2026 SELL
AMZN Amazon.com, Inc. +253,412 Mar 31, 2026 BUY
MSFT Microsoft Corporation -214,820 Mar 31, 2026 SELL
GOOGL Alphabet Inc. -126,000 Mar 31, 2026 SELL
TDG Transdigm Group Incorporated -60,232 Mar 31, 2026 SELL
MCO Moody's Corporation +47,533 Mar 31, 2026 BUY
MA Mastercard Incorporated -19,000 Mar 31, 2026 SELL
V Visa Inc. -18,000 Mar 31, 2026 SELL
MSFT Microsoft Corporation -486,910 Dec 31, 2025 SELL
AMZN Amazon.com, Inc. -243,719 Dec 31, 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 3.5% 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 165 total transactions) suggest a highly active approach to portfolio management, with frequent strategic adjustments and position changes.

Additional Analysis

Complete Holdings

View all 8 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 Mar 31, 2026 reflects a strategic approach to equity investing with 8 holdings valued at $4.1B. 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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