AltaRock Partners Q1 2026 13F Holdings and Activity Report

I. Institutional Overview

As of the portfolio snapshot date of March 31, 2026, the investment landscape for AltaRock Partners, LLC, under the stewardship of Mark T. Massey, reveals a masterclass in high-conviction, concentrated institutional investing. Managing a total portfolio market value of approximately $4.13 billion , the firm maintains an extraordinarily lean profile with only 8 holdings . This level of concentration is rare in the modern institutional world, where many funds of similar size often diversify across fifty to one hundred different securities. AltaRock’s strategy is the antithesis of "closet indexing"; it is a deliberate, surgical approach to capital allocation that prioritizes deep fundamental understanding over broad market exposure.

This section shows only part of the complete report. View the app for the full analysis, position-level detail, and quarter-over-quarter tracking.

II. Sector Allocation Analysis

The Consumer Discretionary sector, at 38.31% , is the undisputed cornerstone of the portfolio. This is primarily driven by a massive position in AMZN (Amazon.com, Inc.) . By allocating nearly 40% of the entire fund to this sector, AltaRock is signaling a profound belief in the resilience of the digital economy and the "platformization" of global commerce. This is not a bet on cyclical retail, but rather a bet on the infrastructure of modern life. The increase in this sector’s weight this quarter suggests that the firm views the current consumer environment as robust, or more likely, that it views its specific holdings within this sector as having "all-weather" characteristics that can withstand inflationary pressures or shifts in discretionary spending.

This section shows only part of the complete report. View the app for the full analysis, position-level detail, and quarter-over-quarter tracking.

III. Top 10 Holdings Deep Dive

The logic behind this massive allocation is likely twofold. First, Amazon Web Services (AWS) continues to serve as the backbone of the global cloud infrastructure, a sector that AltaRock likely views as a utility-like necessity with high growth potential in the AI era. Second, the retail division’s transition toward higher-margin advertising and logistics services has transformed the company’s cash flow profile. By increasing its stake, AltaRock is signaling that it believes Amazon’s valuation still does not fully reflect its long-term earnings power. This is a "double down" on a global winner, suggesting that the firm sees Amazon as the safest and most productive place to park nearly 40% of its capital.

This section shows only part of the complete report. View the app for the full analysis, position-level detail, and quarter-over-quarter tracking.

IV. Major Buys/Additions

The motivation here appears to be a "growth acceleration bet." By the first quarter of 2026, the market's understanding of AI's impact on cloud infrastructure has likely matured. Amazon, through AWS, is a primary beneficiary of this trend. Furthermore, Amazon's logistics network has reached a level of efficiency that allows it to capture a larger share of the "last-mile" delivery market, effectively turning a cost center into a competitive moat. AltaRock is likely looking past the cyclicality of consumer spending and focusing on the structural shift toward digital services. Adding $52 million at an average reported price of $208.27 suggests the firm believes the stock is still in a "valuation trough" relative to its future cash flow potential. This is a classic "buy the winner" strategy, where capital is funneled into the asset with the highest perceived certainty of long-term compounding.

This section shows only part of the complete report. View the app for the full analysis, position-level detail, and quarter-over-quarter tracking.

V. Major Reductions and Rebalancing Operations

The motivation here is likely a fundamental shift in the firm's view of the travel and hospitality sector. Hilton has been a strong performer, but by early 2026, the "revenge travel" cycle may have fully played out, and valuations in the hotel sector might be stretched. By exiting this position so aggressively, AltaRock is signaling that it no longer sees Hilton as a "top 8" idea. This move provided the bulk of the cash used for other operations this quarter, suggesting that the firm found better risk-adjusted returns in the digital infrastructure of Amazon than in the physical infrastructure of hotels.

The 74.38% reduction in Alphabet, realizing $36.23 million , follows a similar logic to the Hilton move. Alphabet’s weight dropped from 1.04% to a negligible 0.30%. This appears to be an "Error-Correcting Exit" or at least a total loss of conviction. In the battle for AI supremacy and search dominance, AltaRock has clearly chosen Microsoft and Amazon over Alphabet. The firm is effectively "cleaning up" the tail end of its portfolio, removing names that no longer meet its stringent criteria for a top-tier holding.

This section shows only part of the complete report. View the app for the full analysis, position-level detail, and quarter-over-quarter tracking.

VI. Investment Insights and Risk Warnings

The logic chain is clear: 1. Sold what: High-valuation tech (Microsoft), peaking travel (Hilton), and losing search (Alphabet). 2. Why sell: To harvest gains and eliminate positions where the long-term "moat" thesis has weakened or the valuation has outpaced the fundamentals. 3. Bought what: More Amazon and more Moody's. 4. Why buy: To double down on the "toll-booth" and "platform" models that provide the highest certainty of cash flow in a digital-first economy. 5. Overall change: The portfolio has become even more concentrated, with the top two holdings now accounting for nearly 64% of the total fund.

For retail investors, the reference value here is the importance of business quality over quantity . AltaRock’s success is built on the idea that you don't need many ideas to build wealth; you just need a few great ones and the courage to hold them in massive size. However, this strategy is not for the faint of heart. The "reference value" for an individual is the firm's focus on pricing power and proprietary infrastructure . In an inflationary or volatile environment, companies like TransDigm and Moody's have the structural ability to pass on costs and maintain margins—a key insight for any long-term investor.

This section shows only part of the complete report. View the app for the full analysis, position-level detail, and quarter-over-quarter tracking.

Sources and limitations

This report uses public U.S. Securities and Exchange Commission Form 13F disclosures and structured data maintained by 13F Hub. A 13F filing is a quarter-end snapshot of reportable long positions, is normally published with a delay, and does not disclose every short position, cash balance, bond, derivative, or non-U.S. asset.

Narrative content is prepared from the same-period SEC disclosure and 13F Hub structured data, then checked before publication. This material is for research and education, not personalized investment advice.