Marathon Asset Management

Marathon Asset Management

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.