Mark Massey's Top Holdings: Dominance in Tech and Industrials as of March 31, 2026
Mark Massey's portfolio, valued at $4.13 billion as of March 31, 2026, is heavily concentrated in Amazon, Transdigm, and Microsoft, with significant allocations across other sectors.
As of March 31, 2026, Mark Massey's portfolio at AltaRock Partners stands at a substantial $4.13 billion. His investment strategy clearly favors large-cap technology and industrials, with Amazon.com Inc. (AMZN) leading the portfolio allocation at 38.2%, followed closely by Transdigm Group Inc. (TDG) at 25.54% and Microsoft Corp. (MSFT) at 16.75%. These three holdings alone account for nearly 80% of the total portfolio value, showcasing a concentrated approach.
Amazon.com Inc. (AMZN), the giant in e-commerce and cloud computing, is not only the largest holding but also showed an increase in shares held by the investor, growing by 3.46% compared to the previous period. This suggests ongoing confidence in the company's prospects. Investors can learn more about Mark Massey's investment profile by visiting his profile on Insiderset: Mark Massey at Insiderset. For detailed information about Amazon.com Inc., please see: AMZN on Insiderset.
Transdigm Group Inc. (TDG), a key player in the industrials sector specializing in aircraft and defense systems, holds the second-largest position. However, the investor reduced their stake in Transdigm by 6.21%, indicating a potential strategic shift or reassessment of the company's outlook. Further details on Transdigm Group can be found at: TDG on Insiderset.
Microsoft Corp. (MSFT) experienced a significant reduction in its share count, with the investor cutting holdings by 10.32%. Despite this decrease, Microsoft remains a cornerstone of the portfolio at 16.75% allocation. More information about Microsoft Corp. is available at: MSFT on Insiderset.
The remaining portfolio is diversified across several other sectors, including Financial Services and Communication Services. Moody's Corp. (MCO) and Mastercard Inc. (MA) are both significant holdings in the Financial Services space, representing 9.11% and 6.33% of the portfolio respectively. Moody's saw an increase in its share count, while Mastercard saw a slight decrease. For Moody's Corp., visit: MCO on Insiderset. Mastercard Inc. details are here: MA on Insiderset.
In the Financial Services sector, Visa Inc. (V) also holds a notable position, albeit smaller at 3.65%. The investor reduced their stake in Visa by 3.48%. Learn more about Visa Inc. at: V on Insiderset.
The investor also holds smaller positions in other companies like Alphabet Inc. (GOOGL) and Hilton Worldwide (HLT), representing 0.3% and 0.11% of the portfolio respectively. Alphabet saw a massive reduction in holdings, while Hilton Worldwide saw nearly a complete liquidation. Details on Alphabet can be found at: GOOGL on Insiderset.