John O’Callaghan serves as an Advisor at Horizon Capital, where he leads capital formation, manages investor relationships, and develops strategic partnerships with family offices and institutional investors across the United States.

With over two decades of experience in investment management, business development, and client relations, John has raised and structured significant capital across alternative and direct investment strategies. His past roles include raising $153 million in mortgage portfolio acquisitions for Quarry Capital Partners, securing a $100 million clean energy investment mandate, and helping establish a $50 million LP platform at The Incubation Factory built around university-licensed intellectual property. He also co-founded Concordia Capital alongside senior executives from Morgan Stanley and Paine Webber, developing a strategic relationship with CalPERS through its Manager Development Program.

John brings to Horizon Capital a unique blend of institutional fundraising expertise, deep family office relationships, and a proven ability to structure and scale investment platforms. His career reflects a consistent focus on innovation, partnership, and long-term value creation.

He holds an MBA from Boston College’s Carroll Graduate School of Management and a BA from Tufts University. Outside of work, John has advised organizations such as Whitelight Media Group, Taurus Investment Holdings, and the Nexus Global Youth Summit, and served on the Salvation Army’s Kroc Center Committee in Boston.