AltaRock Partners
AltaRock Partners
AltaRock Partners (AltaRock Partners) discloses a $4.13B portfolio across 8 US-listed positions in the latest 13F filing (2026Q1, filed May 15, 2026). The largest holding is AMZN at 38.2% of the book. The biggest move of the quarter: trimmed the GOOGL share count by 74% (position now $12M). Latticework's clone backtest puts this 13F book at +3.3%/yr vs SPY over 11.2 years.
About AltaRock Partners
AltaRock Partners is a Boston-based concentrated long-only equity manager founded by Jim Goetz and John Melas-Kyriazi, running what amounts to a high-conviction compounding portfolio: eight disclosed positions at last count, with the top five accounting for roughly 96% of a $4.1B book. The style sits in the Munger-influenced "wonderful businesses at fair prices" tradition — Amazon, TransDigm, Microsoft, Moody's, and Mastercard have been persistent core holdings, each chosen for durable pricing power and reinvestment runway. There are no known short positions, options overlays, or derivatives strategies that would create material divergence between the 13F and the actual portfolio; what you see is largely what they own. The 45-day disclosure lag is the primary friction for anyone attempting to clone the book — position-level changes can be meaningful given how few names are held, so a quarterly filing may already reflect a full turn in one of the top weights.
2026Q1 brief
AltaRock's $4.1B book sits in just 8 positions with a 95.9% top-5 concentration — one of the most extreme in the super-investor universe — and this quarter saw virtually no structural change, which is itself the message. The only moves were aggressive trims to what were already rounding-error positions: GOOGL cut 74% to just 0.3% of the portfolio, and HLT slashed 97% to a barely visible 0.1%. These are effectively staged exits, likely completing the liquidation of legacy or exploratory stakes. The core quartet of AMZN (38.2%), TDG (25.5%), MSFT (16.8%), and MCO (9.1%) held completely steady, underscoring AltaRock's conviction-driven, low-turnover philosophy. MA (6.3%) and V (3.7%) fill out the fintech payments exposure. The portfolio is essentially a thesis on durable compounders with pricing power — aerospace aftermarket, payments rails, cloud, and financial data. Watch next quarter whether GOOGL and HLT are fully closed out, and whether any proceeds fund a meaningful new position or add to the existing core.
AI-generated. Not investment advice.
In the news
all news →No recent news mentions of AltaRock Partners.
Headlines via Google News. Links open in a new tab.
Holdings (8) · click any column to sort
| #↑ | Ticker | Issuer | % Port. | This Q | History | Value |
|---|---|---|---|---|---|---|
| 1 | AMZN | 38.2% | $1.58B | |||
| 2 | TDG | 25.5% | $1.05B | |||
| 3 | MSFT | 16.8% | $691M | |||
| 4 | MCO | 9.1% | $376M | |||
| 5 | MA | 6.3% | $261M | |||
| 6 | V | 3.7% | $151M | |||
| 7 | GOOGL | 0.3% | $12M | |||
| 8 | HLT | 0.1% | $5M |
- 1AMZNport38.2%val$1.58BAmazon.com Incthis Q hold·17q
- 2TDGport25.5%val$1.05BTransdigm Group Incthis Q hold·40q
- 3MSFTport16.8%val$691MMicrosoft Corpthis Q hold·20q
- 4MCOport9.1%val$376MMoody's Corpthis Q hold·40q
- 5MAport6.3%val$261MMastercard Inc - Athis Q hold·40q
- 6Vport3.7%val$151MVisa Inc-class A Sharesthis Q hold·40q
- port0.3%val$12MAlphabet Inc-cl Athis Q -74%·26q
- 8HLTport0.1%val$5MHilton Worldwide Holdings INthis Q -97%·6q
All activity (2026Q1)
| Ticker | Issuer | Move | % Port. | Δ Shares | Value |
|---|---|---|---|---|---|
| HLT | Hilton Worldwide Holdings IN | TRIM | 0.1% | -97% | $5M |
| GOOGL | Alphabet Inc-cl A | TRIM | 0.3% | -74% | $12M |
- TRIMHLT0.1%Hilton Worldwide Holdings INΔ -97%·$5M
- TRIMGOOGL0.3%Alphabet Inc-cl AΔ -74%·$12M
Frequently asked questions
- What stocks does AltaRock Partners own?
- As of 2026Q1, AltaRock Partners's 13F discloses 8 positions worth $4.13B. The top five holdings: AMZN (38.2%), TDG (25.5%), MSFT (16.8%), MCO (9.1%), MA (6.3%). 13F filings cover long US-listed equities only — cash, bonds, shorts, and non-US positions are not disclosed.
- What did AltaRock Partners buy this quarter?
- The 2026Q1 filing shows no new purchases — no new positions were opened and no existing holdings were added to this quarter.
- How big is AltaRock Partners's portfolio?
- $4.13B across 8 positions per the latest 13F (filed May 15, 2026). The top five holdings account for 96% of the disclosed book.
Explore more
Long US equity 13F-HR filings only — no shorts, no derivatives. SEC filings at EDGAR (CIK 0001631014). Not investment advice.