Mark Massey's Concentrated Portfolio Dominated by Amazon and Transdigm
Mark Massey's portfolio as of March 31, 2026, shows significant concentration in Amazon and Transdigm, with notable changes in holdings.
As of March 31, 2026, Mark Massey's portfolio managed through AltaRock Partners displays a concentrated profile, heavily weighted towards a few key holdings. This analysis focuses on the largest positions and their recent share changes.
The largest position is Amazon.com Inc. (AMZN), representing approximately 38.2% of the total portfolio value of $4.13 billion. The position saw an increase in shares during the prior period, with a positive change in shares and a positive change percentage of 3.46%. Investors can learn more about Mark Massey's investment approach by visiting his profile at https://www.insiderset.com/investor/mark-massey-altarock-partners and explore the stock details for Amazon at https://www.insiderset.com/investors/stocks/AMZN.
Transdigm Group Inc. (TDG) is the second-largest holding, accounting for 25.54% of the portfolio. This position in the Industrials sector experienced a decrease in shares (-6.21%) during the prior period, indicating a reduction in exposure.
Microsoft Corp. (MSFT) and Moody's Corp. (MCO) follow as the third and fourth largest holdings, representing 16.75% and 9.11% of the portfolio respectively. Microsoft shares also decreased (-10.32%), while Moody's saw an increase (+5.84%) in shares during the prior period.
Other significant positions include Mastercard Inc. (MA) and Visa Inc. (V), both in the Financial Services sector, holding 6.33% and 3.65% of the portfolio respectively. Mastercard shares decreased (-3.51%) while Visa shares also saw a decline (-3.48%).
The portfolio also includes smaller positions in Alphabet Inc. (GOOGL) and Hilton Worldwide (HLT), representing 0.3% and 0.11% of the total value. Alphabet shares experienced a substantial decrease (-74.38%) in the prior period, while Hilton shares saw a near-total reduction (-97.17%).
Overall, Mark Massey's portfolio exhibits significant concentration in a small number of stocks, particularly in Amazon and Transdigm. The changes in share counts for these and other holdings during the prior period reflect dynamic adjustments within this concentrated strategy.