# Marathon Asset Management Marathon Asset Management is an Asset Manager based in New York, United Kingdom. ## Overview - **Organization type:** Asset Manager - **Headquarters:** New York, United Kingdom - **Region:** Europe - **Address:** London, United Kingdom - **Founded:** 1986 - **Assets under management:** Undisclosed - **Website:** www.marathonfund.com - **LinkedIn:** https://www.linkedin.com/company/marathon-asset-management - **Wikidata:** Q6754999 ## Regulatory record - **CRD number:** 124613 - **SEC file number:** 801-61792 - **Registration status:** APPROVED - **Latest Form ADV filing:** 2026-03-31T05:00:00.000Z - **Reports private funds:** Yes - **Private funds reported:** 0 - **IAPD record:** https://adviserinfo.sec.gov/firm/summary/124613 ## About The firm was founded in London in 1986 by Jeremy Hosking, Neil Ostrer and William Arah, who met as investment managers at GT Management. Marathon's intellectual foundation rests on a capital cycle approach to investing, articulated in their internal strategy letters and the subsequent book *Capital Returns*. The framework analyses how competitive supply-side dynamics — rather than demand forecasting — drive long-term equity returns. Marathon runs concentrated global and regional equity portfolios, with sector specialists operating as generalists within their coverage areas. The firm invests across the market-cap spectrum, holding positions through full capital cycles that typically span three to five years. Portfolio construction avoids explicit benchmark weights; position sizing reflects conviction in the capital cycle thesis. The manager's European and global strategies have been available to institutional investors for decades, while an Irish-domiciled UCITS fund extends access to a broader allocator base. The firm operates from a single London office. Marathon has historically imposed a soft close or hard close on strategies when capacity limits are approached, a practice intended to preserve the concentration and long-term horizon of its investment process. Team size and assets under management are not publicly disclosed. The founding generation began transitioning leadership responsibilities in the late 2010s, with portfolio managers who joined the firm in the 1990s and 2000s assuming greater oversight of investment functions. Marathon's structural differentiator is its orthodox adherence to a single, internally developed analytical framework across all strategies. The capital cycle philosophy permeates hiring, portfolio construction and client communication. The firm publishes lengthy quarterly letters that do not market performance but instead teach the capital cycle lens through detailed case studies, a practice that functions as both investor education and a filter for selecting like-minded allocators. ## Questions ### How does Marathon construct its portfolios? Portfolios are built bottom-up by sector specialists, each running a concentrated book of roughly 10 to 25 names. Position sizing is driven by conviction in the capital cycle thesis rather than by an index's sector or country weight. The firm runs both global and regional mandates. Marathon has historically soft-closed or hard-closed strategies when approaching internal capacity limits to protect the concentration and investment horizon of the process. ### Does Marathon manage separate accounts or only commingled funds? Marathon manages both commingled funds and segregated mandates for institutional clients. The firm's strategies are available in multiple vehicles, including an Irish-domiciled UCITS fund. Marathon's institutional client base has historically included pension funds, endowments and sovereign wealth funds, though the firm does not publicly disclose its full client list. ### How does Marathon communicate with investors and what sets that communication apart? Marathon publishes lengthy quarterly letters that function more as capital cycle case studies than traditional performance commentary. These letters teach the investment framework through detailed analysis of specific industries and companies, explaining how competitive dynamics evolve when capital enters or exits a sector. The practice serves both as investor education and as a mechanism for attracting allocators who share the firm's long-horizon, supply-side orientation. ## Related profiles - [Maranello Capital](https://altss.com/profile/maranello-capital) - [Marathon Capital Partners](https://altss.com/profile/marathon-capital-partners) --- Last updated: 2026-06-03T20:00:00.000Z Canonical page: https://altss.com/profile/marathon-asset-management Maintained by Altss — https://altss.com — methodology: https://altss.com/methodology