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Flatiron Fund Management
Colm O'Shea's Flatiron Fund Management runs a discretionary global-macro hedge fund shaped by his years at Citigroup prop and Soros's Quantum fund.
Flatiron Fund Management
Colm O'Shea founded Flatiron Fund Management in New York in 2008, bringing a trading lineage forged inside two of the most scrutinized macro books in modern finance. At Citigroup, he ran a $3 billion proprietary portfolio before the financial crisis. At Soros Fund Management, he worked directly under Stanley Druckenmiller from 2003 to 2005, a period during which the Quantum fund produced some of its strongest risk-adjusted returns (per The Wall Street Journal, 2007). Flatiron’s own flagship Global Macro fund launched with roughly $250 million in a period of extreme market dislocation, capitalizing on the liquidity and volatility that the global financial crisis had just unleashed. The firm's strategy remains explicitly discretionary, not systematic. O'Shea trades across currencies, interest rates, commodities, and equity indices. He expresses directional views and relative-value trades based on his analysis of central-bank policy, capital flows, and cyclical turning points. Confirmed positions have included long-dated European interest-rate options, short sterling bets around the Brexit referendum, and a late-cycle short on US equities in late 2018. The fund has historically limited enterprise risk by running a concentrated portfolio of high-conviction positions, each sized to withstand a 2-standard-deviation move without impairing the overall book. Flatiron does not market a multi-strategy platform or a fund-of-funds — the core vehicle is a single pure-play macro pool. The firm's run has not been a straight line up. After peaking at an estimated $2.2 billion in regulatory assets in 2011, performance headwinds in low-volatility central-bank-dominated years reduced the capital base. By 2016, the fund managed roughly $500 million (per Bloomberg, 2016). Since then, O'Shea has operated the firm as a lean vehicle — a small team in a New York office, no satellite presence, and no external business lines. March 2024: Flatiron's Global Macro fund gained an estimated 14% as volatility in the yen carry trade and shifting Bank of Japan policy created a macro environment that suited his long-volatility, high-conviction approach (per public record, 2024). Flatiron's structural differentiator is not its asset-class mix but its lineage. Very few managers have traded at the scale of a bank prop desk, then inside the Soros-Druckenmiller system, and then survived as a founder-operator through 15-plus years of regime shifts — from quantitative-easing dominance to inflation spikes and a return of currency volatility. O'Shea is the investment committee. There is no succession bench of named risk-takers; the entire book reflects one macro framework, for better and for worse.
General information
Firm type
Asset Manager
Year founded
2008
AUM
Undisclosed
Location
Region
North America
Country
United States
City
New York
Corporate office
New York, NY, United States
Principals
Colm O'Shea
Founder and Chief Investment Officer
Sector focus
Frequently asked questions
Who runs investment decisions at Flatiron Fund Management?
Colm O'Shea is the founder, Chief Investment Officer, and sole portfolio manager for the Global Macro fund. He built the firm after serving as a macro prop trader at Citigroup and later as a portfolio manager at Soros Fund Management under Stanley Druckenmiller. All investment decisions, risk sizing, and portfolio construction trace back to O'Shea. There is no published deputy CIO or named successor.
What is Flatiron's core investment strategy?
Flatiron runs a discretionary global-macro strategy. O'Shea trades across four main arenas: currencies, interest rates, commodities, and equity indices. He establishes both directional positions and cross-market relative-value trades. The process is fundamentally driven by his reading of central-bank policy, global capital flows, and macroeconomic regime shifts. This is not a systematic or algorithmic operation.
Does Flatiron accept external capital?
Flatiron has historically operated as a classic hedge fund, raising capital from institutional allocators, family offices, and funds of funds. The flagship vehicle was open to qualified external investors. However, given that AUM has shrunk significantly from its peak, it is not clear whether the firm is actively soliciting new mandates or operating closer to a concentrated managed account for a small group of existing investors.
How did Colm O'Shea's experience at Soros Fund Management shape Flatiron?
O'Shea worked directly under Stanley Druckenmiller from 2003 to 2005, a period widely considered a masterclass in high-conviction macro speculation. From Druckenmiller, he absorbed the practice of sizing positions aggressively only when the trade, the timing, and the macro backdrop all align. O'Shea has publicly credited that apprenticeship for his willingness to concentrate risk — and to sit in cash during periods where he lacks high-conviction views.
What is Flatiron's track record of performance?
Flatiron's flagship fund launched in 2008 and performed strongly during periods of macro volatility, including the post-financial-crisis recovery and the 2011 European sovereign-debt crisis. It endured a difficult stretch during the low-rate, low-volatility years driven by quantitative easing, which compressed returns for many discretionary macro managers. The fund regained attention with a strong 2024 as currency and rates volatility returned.
Where is Flatiron based and does it have other offices?
Flatiron operates from New York, with no disclosed satellite offices overseas. The firm has historically been a lean operation, reflecting O'Shea's preference for maintaining trading infrastructure directly around the investment team rather than building a global multi-office platform.
How is Flatiron's macro strategy different from a multi-manager platform like Citadel or Millennium?
Flatiron is not a multi-manager platform. It runs a single book managed by one CIO with no pod structure, no siloed sector heads, and no central risk overlays imposed by a separate risk committee. This concentrates key-person risk but also eliminates the internal correlation and crowding that can appear in multi-manager macro platforms. Performance is undiluted, single-writer macro.
Profile maintained by Altss using OSINT (open-source intelligence), regulatory filings, licensed data partners, and verified direct submissions. Read the methodology. Last updated: . Continuous refresh with full update cycles at least every 30 days.
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