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Matthew Walsh headshot

Matthew Walsh

Unclaimed
Founding Partner, Castle Island VenturesCastle Island VenturesCambridge, MA

Current Firm

Castle Island Ventures

Focus

Web3, Fintech

About Matthew Walsh

Matthew Walsh is a Founding Partner at Castle Island Ventures, a venture capital firm focused on identifying and supporting transformative companies across Web3, Fintech, DevTools, and Cybersecurity. In his role, Walsh leverages deep expertise in emerging technologies and digital infrastructure to source, evaluate, and mentor portfolio companies navigating rapidly evolving markets. His investment thesis centers on technologies that enhance financial systems, developer productivity, and security infrastructure. As a founding partner, Walsh plays a key role in shaping the firm's investment strategy and building its portfolio across multiple high-growth sectors. His professional network and industry insights guide Castle Island Ventures' commitment to backing entrepreneurs building the next generation of technology solutions.

Focus Areas

Investment Stage

Pre-Seed
Seed
Series A
Series B+

Other Investors at Castle Island Ventures

Hunter Merghart
Hunter Merghart

Venture Partner, Castle Island Ventures

Castle Island Ventures

Ria Bhutoria headshot
Ria Bhutoria

General Partner, Castle Island Ventures

Castle Island Ventures

Sean Judge headshot
Sean Judge

General Partner, Castle Island Ventures

Castle Island Ventures

View full team →

Investment Profile

Matthew Walsh is a Founding Partner, Castle Island Ventures at Castle Island Ventures, based in Cambridge, MA.

Matthew's investment focus spans Web3, Fintech, DevTools, Cybersecurity, primarily investing at the Pre-Seed, Seed, Series A, Series B+ stages. This specialization allows for deep domain knowledge and strong network effects that benefit portfolio companies.

Frequently Asked Questions

Who is Matthew Walsh?

Matthew Walsh is a Founding Partner, Castle Island Ventures at Castle Island Ventures, based in Cambridge, MA. Their investment focus includes Web3, Fintech, DevTools.

What does Matthew Walsh invest in?

Matthew Walsh focuses on investments in Web3, Fintech, DevTools, Cybersecurity through Castle Island Ventures. These focus areas reflect their domain expertise and the types of startups they actively seek to back.

What firm is Matthew Walsh at?

Matthew Walsh is currently at Castle Island Ventures, headquartered in Cambridge, MA, serving as Founding Partner, Castle Island Ventures.

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