Our world

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Our business is about risk, but really, it’s about people. They are the true currency of our success. We embrace diverse views and inquiring minds, and empower our experts to have the courage of their convictions. We care. Because our clients do.

See the team

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We’re building a market-leading platform that’s agile, responsive and future-focused. Blockchain, intelligent automation, straight-through processing—our insurtech system offers end-to-end digital efficiencies benefiting clients and partners every step of the way.

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We’re a network born of trust and tested relationships—connecting a world of investors, clients, brokers, reinsurers and trade-capital partners with tailored risk solutions. The heritage of Lloyd’s accelerates our global reach. We’re also proud to partner with Golden Gate Capital, whose long-term vision helps us build a business to stand the test of time.

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The team

Mosaic creates an innovative environment led by a team with proven experience building global specialty businesses. We foster a high-performance, entrepreneurial ownership culture, where diverse views and talent are integral to our evolution and ultimate business success.

Mitch Blaser

Co-Chief Executive Officer

Based in Bermuda, Mitch Blaser has more than 40 years of accomplishments in international insurance markets.

In 2006, he joined Robert Clements as a founding executive to launch Bermuda-based Ironshore with $1 billion in private-equity capital, and helped drive its growth to become a global property & casualty insurer with over 800 employees in 15 nations. Mitch held key roles during the company's evolution, including COO of Ironshore Inc, CFO and CEO of Ironshore Bermuda, and CEO of Iron-Starr Excess Agency and IronServe. In 2017, Ironshore was acquired by Liberty Mutual Group, where he became Chief Transformation Officer of the company's Commercial Lines division. Formerly, Mitch was CFO, Americas, for Swiss Re, and a member of the leadership team at Marsh Inc, including roles as both Global CFO and Head of Technology & Corporate Services.

Mark Wheeler

Co-Chief Executive Officer

Based in Bermuda, Mark Wheeler is a seasoned executive, Lloyd’s syndicate founder, and market-leading underwriter. He has served in a variety of leadership roles, overseeing capital planning, underwriting and distribution during his more than three decades of industry experience across global markets and product lines.

Mark was the founder of top-quartile Lloyd’s Syndicate 4000 and Pembroke Managing Agency, purchased in 2008 by Ironshore, where his current Co-CEO Mitch was a founding executive. Mark served as CEO of Ironshore International, overseeing creation of high-profile consortia and expansion to 14 countries. He later held executive roles in global client engagement and international markets for Liberty Mutual Group following its 2017 acquisition of Ironshore. Prior to Pembroke, Mark spent 14 years at Lloyd’s as an active underwriter for SVB’s financial lines Syndicate 1007, which became Novae.

Lisa Fontanetta

Chief of Staff​

A senior strategist and one of the founding executives of Ironshore Inc, Lisa served as Ironshore's Head of Strategic Operations, focusing on global financial and strategic initiatives and overseeing capital markets transactions, board reporting, investor relations, and rating-agency management. From 2007 through 2012, Lisa was Ironshore's Global Head of Financial Planning & Analysis. She also served as CFO of IronServe, Ironshore's global outsourcing relationship. While at Liberty Mutual, she was a Lead Transformation Officer for the Commercial Lines Division, Global Risk Solutions. Lisa began her career at Swiss Re America in finance planning and analysis roles.

Krishnan Ethirajan

Chief Operating Officer​

With 25 years of industry experience, Krishnan previously was COO of Ironshore International and IronServe, delivering services to global platforms. He became a Lead Transformation Officer for Liberty Mutual Group's Commercial Lines Division, Global Risk Solutions in 2017. Formerly, Krishnan was Insurance Sector Leader for the Shared Services & Operations practice at PricewaterhouseCoopers. He also held management roles at Allstate Insurance, where he established the Global Sourcing Office and executed its operational transformation programme, and at Gartner, where he managed its Asia and Central US consulting group.

Oz Haque

Chief Financial Officer​

A finance and M&A professional with 20 years of investment banking experience, Oz has focused on the insurance industry through most of his career. Before joining Mosaic, he was a Managing Director at boutique investment bank Foros, concentrating on mergers and acquisitions across industries. Prior to that, he was a Director in the Financial Institutions Group at Deutsche Bank, advising on company acquisitions and sales, and capital raises. Oz started his investment banking career at Lazard focusing on financial services, after research roles at the World Bank and International Finance Corporation.

Chris Brown

EVP, Syndicated Capital Management

Chris brings 35 years of Lloyd's market experience to Mosaic. Most recently, he served as Strategic Partnership Director, Hamilton Insurance Group, following its acquisition of Pembroke Managing Agency. He joined Syndicate 4000 at inception in 2004 to lead the Financial Institutions Division and was a Founding Director of Pembroke in 2006. He led the managing agency's provision of services to Lloyd's Syndicates 2014, 1947 and 6125 from 2014. Prior to joining Pembroke, Chris spent 10 years as a Financial Institutions underwriter at Lloyd's. He began his career at Robert Fleming Insurance Brokers.

Charles Mackay

EVP, Active Underwriter, Syndicate 1609

Charlie has spent 20 years in the Lloyd's insurance market as an underwriter, with a strong track record across product lines and experience in finance, actuarial, distribution, regulatory and group reporting functions. Most recently, he was Co-Deputy Active Underwriter, Head of Specialty, for Hamilton Managing Agency in 2020, and previously worked as Active Underwriter for Pembroke Managing Agency's Syndicate 4000. Prior, he spent 10 years as Divisional Director, Political Risks, with the same Pembroke syndicate, founding and leading the division.

Kyoko Tsuru

Chief HR Officer

Kyoko has over 20 years of HR experience, serving in management and leadership positions at Fortune 100 companies in the US, Latin America and Europe, including Citigroup and PepsiCo. She served as Head of HR for the International Division of Ironshore and, previously, was HR Leader at Guy Carpenter for four years until 2016. Most recently, she worked in her own private practice as an executive coach, HR consultant, and advisory board member for two corporate startups.

Olly Reeves

Group Chief Risk Officer

Olly was formerly Chief Risk officer for Neon Underwriting, responsible for various functions including risk management, compliance, capital modelling and underwriting management; he also helped the turnaround of its legacy business. Previously, Olly was Head of Risk Management at Lloyd's of London, with responsibility for oversight of the market across minimum standards, Solvency II model compliance, and administration of Lloyd's own risk-management framework. Prior to Lloyd's, Olly was a Manager in the Financial Services Risk Management division at Ernst & Young.

Rosemary Jones

Chief Communications Officer

An author and former journalist, Rosemary joins Mosaic after six years with national public-private agencies, driving public-relations strategy, brand building, social media and thought leadership. As Director of Corporate Communications & Strategy at the Bermuda Tourism Authority, she managed media and stakeholder relations and oversaw the National Tourism Plan. Previously, she was Head of Communications & Marketing for the Bermuda Business Development Agency, which supports the island's global financial services sector in attracting investment and new business.

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