Mark Massey's December 2025 Portfolio Update

Mark Massey, managing director at investment firm AltaRock Partners, saw his $5.1 billion portfolio reach its December 31, 2025 value.

His largest holding, Amazon.com Inc (AMZN), saw a reduction of 3.22% in its portfolio allocation, while Microsoft Corp (MSFT) decreased by 18.95%. Moody's Corp (MCO) and Mastercard Inc (MA) also experienced notable share reductions.

Significant changes occurred in his portfolio, including a substantial 50.81% reduction in Alphabet Inc (GOOGL) shares and a decrease in Transdigm Group Inc (TDG) by 0.72%. Other holdings like Visa Inc (V) and smaller allocations like Alphabet Inc (GOOGL) also saw decreases.

For detailed analysis of these holdings, including market caps and financials, visit the investor profiles: Mark Massey at Insiderset and individual stock profiles like AMZN, GOOGL, and others.