Mark Massey - AltaRock Partners Portfolio (Jun 30, 2025)


As of Jun 30, 2025, the AltaRock Partners oversees a portfolio valued at approximately $5.48B, featuring 9 publicly traded holdings. This in-depth profile highlights the top investments led by Microsoft (MSFT), Berkshire Hathaway (BRK-B), Waste Management (WM), and others—drawing on its latest SEC filings as of Aug 14, 2025. Explore insights into portfolio composition, allocation strategies, and recent trade activity.

Balances
Holdings
Activity
Options
Allocation
Strategy

AltaRock Partners Strategy Analysis

Investment Strategy Metrics

Key metrics revealing investment style, risk management, and performance characteristics

MetricValueCategoryDescription
Holding Period2.3 yearsStyleAverage duration positions are maintained
Position Count10StyleNumber of active positions in portfolio
Position Size11.7%RiskTypical allocation per position
Win Rate65.5%PerformancePercentage of profitable positions
Average Return9.8%PerformanceMean return across positions
Sharpe Ratio0.23PerformanceReturn per unit of risk taken

Investment Case Study: TRANSDIGM (TDG)

12/31/2014 - 9/22/2025

Performance Metrics

Total Return: 66.46%

Holding Period: 3918 days

Max Position Size: $50,688.00

Position Weight: 25.26%

Key Events

12/31/2014: ENTRY(155,084.00 shares) @ $0.20
3/31/2015: INCREASE(76,666.00 shares) @ $0.22

Investment Thesis

Entry Context: Initial position established based on fundamental analysis

Sector Conditions: Favorable market conditions in the sector

Risk Factors:
  • Market volatility
  • Sector-specific risks

Key Learnings

  • Position sizing is critical for portfolio management
  • Important to monitor sector exposure

Sector Allocations