Bermuda-based specialty re/insurer Hamilton has appointed Marc Roston (pictured above) to its board of directors as a shareholder director, placed by Magnitude Capital, the company’s single largest shareholder.
The move, effective February 20, sees Roston replace Hawes Bostic on the Hamilton board.
Roston brings more than 30 years of experience as an investment professional, with stints advising hedge funds, insurers, and family offices through MNR Capital, his own advisory firm, since 2009. He is also a Senior Research Scholar at Stanford University and an Operating Partner at private equity firm DFW Capital Partners.
Magnitude Capital, which placed Roston on the board, is a New York-based multi-strategy hedge fund that has managed global portfolios for over two decades. SEC filings show it holds a 15% stake in Hamilton across multiple fund vehicles, including Magnitude Master Fund, Magnitude Partners Master Fund, and Magnitude Insurance Master Fund – all in Class B common shares.
The firm's total assets under management stand at roughly US$2.25 billion, estimates from Wall Street Oasis indicate.
Hamilton chair David A. Brown said he was confident Roston's experience would enhance the board's effectiveness.
"I extend my gratitude to Hawes for serving on our Board and for his invaluable support in the pivotal growth years during the lead-up to and following our listing on the New York Stock Exchange," Brown said.
Under Hamilton's governance framework, shareholders holding at least 5% of outstanding common shares may appoint a director. Hopkins Holdings exercised the same right in June 2024 when it placed Bradley E. Cooper on the board, meaning Magnitude Capital is rotating its representative rather than expanding its influence.
The Marc Roston appointment extends a busy stretch of governance and executive changes since Hamilton went public on the NYSE in November 2023.
In May 2025, Karen Green and David Priebe joined the board. A month later, the company reshuffled its executive ranks, naming Adrian Daws as CEO of Hamilton Re and Alex Baker as CEO of Hamilton Global Specialty.
By October, new board chairs had been installed at Hamilton Global Specialty, and in January, Michelle Li was appointed CFO of the same unit. Earlier this month, Moussa Thiam was promoted to Group Head of Compliance – a move Hamilton explicitly tied to strengthening governance as a publicly listed firm.
In total, the company has rotated or added board members at least five times and overhauled C-suite roles across all three underwriting platforms in roughly 27 months. This pace that reflects a business working to professionalize its infrastructure as gross premiums have swelled from US$571 million in 2018 to US$2.9 billion in 2025.
The appointment also came the same day Hamilton reported its full-year 2025 results, posting net income of US$577 million – a 44% increase year-on-year – with return on average equity of 22%. The board also declared a special dividend of US$2.00 per share, totaling about US$206 million.
