Castle Island Ventures
Venture capitalActively deployingBoston · Pre-Seed–Series A · 12 people tracked
Investment thesis
Castle Island Ventures invests in early-stage companies at the intersection of traditional finance and public blockchains. The firm believes blockchain technology can enable frictionless finance and is committed to backing infrastructure and applications that unlock the transformative potential of these protocols.
Source: firm website, verified Jul 21, 2026.
Team · 12 people
from the firm's websiteFounding Partner focused on infrastructure investments in financial services, enterprise software, and cybersecurity. Previously Vice President at Fidelity Investments leading blockchain and cryptoasset initiatives. Holds BS in Business Administration from Babson College and MBA from Duke University's Fuqua School of Business.
Founding Partner and cofounder of Coin Metrics. Previously worked at Fidelity as their first cryptoasset analyst, developing research perspectives on public blockchains. Holds degree in philosophy from University of St Andrews and MSc Finance and Investment from University of Edinburgh.
Chief Legal Officer with career spanning private practice, government, and technology. Previously served as acting general counsel of U.S. Department of Homeland Security managing 1,700 lawyers on national security matters. Private-sector experience includes chief legal officer of Circle, general counsel of Paradigm, partner at True Ventures, and partner at Goodwin Procter. Teaches Artificial Intelligence: Law and Policy at Boston College Law School. Holds J.D. from Cornell Law School and B.A. from Colgate University.
General Partner with prior experience as Managing Director at Steadfast Financial leading cryptoasset investing. Previously convertible arbitrage trader at Admiral Capital. Holds BA in Politics from Princeton University and MBA from Saïd Business School at University of Oxford.
General Partner focused on financial market infrastructure, consumer fintech, and blockchain-powered applications. Board member at Felix, Eaglebrook Advisors, Cyclops, Valinor Digital, and XFX. Previously Principal at Highland Capital Partners and investor at Pomona Capital. Started career as investment banker at Bank of America Merrill Lynch. Holds BA in Economics from Vanderbilt University.
Venture Partner currently serving as Chief Operating Officer for Digital Assets at a multi-manager hedge fund. Previously Head of US at Bitstamp establishing and growing the regulated crypto exchange's U.S. presence. Earlier served as Head of Trading at Coinbase starting the institutional trading desk and helping establish the New York office. Career began as equity trader at Barclays, RBC, and Credit Suisse. Holds BA in Economics from Colgate University.
Venture Partner with expertise in digital asset research. Previously Director of Research at Fidelity Digital Assets focusing on bitcoin and digital assets, and Senior Research Analyst at Circle building the Circle Research platform. Early career included Equity Research Associate on Fintech and Payments team at Credit Suisse. Holds BS in Finance from New York University Stern School of Business.
Controller responsible for finance, accounting, and operations across the firm. Previously Controller at New Heritage Capital overseeing fund finance and operations. Earlier held roles at Energy Impact Partners managing portfolio valuation and fund accounting, and at Flagship Pioneering and Ultimus LeverPoint. Holds B.S. in Actuarial Science and B.S. in Accounting from Siena University.
CFO with over two decades in venture capital. Responsible for finance and operations at Castle Island. Previously Director of Finance and Operations at B-FLEXION US managing a $2 billion health care fund's U.S. entity, and held CFO and VP of Finance roles at Atlas Venture and Accomplice. Early career included controller positions at Globespan Capital Partners and NVest Companies. Holds MBA/MS in Accounting from Northeastern University and BA from Colby College.
Investor previously employed as data scientist at BAM Elevate supporting growth stage investments in fintech and enterprise software. Earlier served as equity research analyst at M Science covering the consumer sector. Holds BA in Computer Science from University of Virginia.
Executive Assistant to the Partners joined in 2022. Previously spent five years as Executive Assistant at Ocean Spray Cranberries supporting C-suite executives and managing Finance and Technology office operations. Earlier served as Executive Assistant at Sonesta Hotels supporting the CEO. Holds B.A. in Communication Studies from Bridgewater State University and is a licensed esthetician.
Investor focused on building and expanding the onchain economy. Joined the firm in 2023 with crypto industry experience since 2021, previously serving as investment analyst at Shima Capital. Holds BA in Political Science from Williams College.
What they invest in
from 15 of 29 portfolio companiesCrypto & Web3 ×12Fintech ×10Enterprise Software ×4SaaS ×4Cybersecurity ×2AI & Machine Learning ×1B2B Marketplaces ×1Biotech ×1
HQs:United States×6United Kingdom×1
Investments · 29 tracked
founders shown can be your intro pathA DeFi protocol creating a marketplace for blockspace.
Alpen Labs builds a Bitcoin layer-2 network that enables financial applications through a ZK rollup with optimistic bridge architecture. It allows users to borrow against Bitcoin, earn interest, and transact in dollars while settling transactions directly on Bitcoin.
Crypto & Web3Fintech
John LightTrey Del BonisLiam EagenManish Bista
Tools offering users secure financing against their cryptocurrency holdings.
ARQ Finance (formerly DolarApp) is a digital financial platform that enables currency exchange to digital dollars and euros, international payments, and investment access to global markets. It serves individuals seeking low-cost cross-border transactions and international investment opportunities.
Crypto & Web3FintechLondon, GB
Fernando Terrés(CEO and co-founder)inZach Garman(Founder)inAlvaro Correa(Founder)in
Arx develops secure chips that embed blockchain authentication into physical items like apparel, collectibles, and certificates, enabling decentralized provenance verification and digital experiences without centralized servers.
Crypto & Web3Deep TechHardware
Delivers decision-grade intelligence on U.S. banks by integrating regulatory filings, securities data, and property deed information.
Babylon Labs develops trustless infrastructure that enables Bitcoin to be used as collateral in decentralized finance and through a Bitcoin staking protocol for blockchain validation. The platform allows users to lock native Bitcoin without wrapping or custodial risk.
Crypto & Web3
A Bitcoin restaking solution that extends Bitcoin security to other blockchains.
A global payments network enabling consumers and businesses to transact in any currency, anywhere on earth.
Bitwise Investments provides professionally managed cryptocurrency funds and investment products for institutional and individual investors. The company offers a suite of crypto-focused solutions including ETFs, separately managed accounts, private funds, and staking products.
Crypto & Web3FintechSan Francisco, US
Felix is a remittance service that enables users to send money from the United States to Latin America (Mexico, Guatemala, Honduras, El Salvador, and Dominican Republic) via WhatsApp, with funds delivered to bank accounts, mobile wallets, or cash pickup locations.
B2B MarketplacesFintech
Andrena is a wireless Internet service provider that delivers high-speed connectivity to multi-tenant buildings and households using wireless technology beamed to building roofs, then distributed wirelessly to units. The company serves building owners, tenants, and residential customers seeking affordable Internet alternatives to traditional cable and fiber infrastructure.
CleantechCloud ComputingNew Jersey, US
Modern Treasury provides a payments infrastructure platform that enables businesses to move and track money across fiat and stablecoin rails through a single API. The company serves enterprises and financial service providers looking to streamline payment operations across multiple currencies, regions, and payment systems.
Crypto & Web3Enterprise SoftwareFintechSaaSSan Francisco, US
Matt Marcus(Co-Founder & CEO)inDimitri Dadiomov(Cofounder & CEO)inSam Aarons(Co-Founder & CTO)in
Ripple builds blockchain-based financial infrastructure to enable cross-border value transfer and payment solutions for enterprises, governments, and financial institutions. The company develops products and public blockchain technology (XRP Ledger) used by hundreds of customers across over 50 countries to facilitate payments, liquidity access, and financial inclusion.
Crypto & Web3Enterprise SoftwareFintech
Station70 builds institutional-grade security products for enterprise asset protection, including private key backup and recovery (Bunker) and secrets management (Gatekeeper). The company serves enterprises that depend on critical assets like keys, identities, and access controls, using zero-knowledge cryptography and hardware security modules.
Crypto & Web3CybersecurityEnterprise Software
Talos provides white-label cryptocurrency trading infrastructure and technology for retail investment platforms and digital asset brokerages. The platform enables customers to aggregate liquidity from multiple exchanges and OTC desks, manage trading workflows, and deliver branded trading experiences to end users.
Crypto & Web3Data & InfrastructureFintechSaaS
Tesser provides stablecoin infrastructure and settlement solutions for financial institutions, enabling them to manage payments, treasury, and cross-border transactions while maintaining customer relationships and regulatory compliance. The platform offers wallet infrastructure, on/off-ramps, and APIs for institutions to deploy stablecoin payments at scale.
Crypto & Web3FintechSaaS
TRM Labs offers an online certification course on blockchain investigations and crypto forensics for professionals who need to trace cryptocurrency transactions across multiple blockchains. The course covers cryptocurrency essentials, financial crime risks, on-chain investigation techniques, and crypto compliance using TRM Labs' forensics tools.
Crypto & Web3CybersecurityEdTechEnterprise SoftwareFintechGovTechSan Francisco, US
Sujit Raman(Chief Legal Officer)Ali Comolli(Global Capacity Building Lead)Ari Redbord(Global Head of Policy)Tom Armstrong(Head of Compliance Advisory)
Valinor Discovery generates patient-derived datasets combining multi-omics and clinical data to enable machine learning applications in drug development. The company collects longitudinal data across molecular and imaging assays to create virtual patient profiles for pharmaceutical research.
AI & Machine LearningBiotechMedical Devices
Provides AI-powered content detection and digital media forensics to validate the authenticity of media content.
XFX is a liquidity layer that enables institutions to move money across fiat and stablecoin pairs with intelligent routing, instant settlement, and no required capital pre-positioning. The platform serves financial institutions and teams building fintech infrastructure.
Crypto & Web3FintechSaaS
Board seats · per SEC filings
what is this? ⓘ$90.7M raise · filed Nov 2024 · via Gus D Coldebella
Inferred from directors named on each company's SEC Form D — public regulatory data, not a portfolio list published by the firm.
Frequently asked questions
- What stage does Castle Island Ventures invest at?
- Castle Island Ventures invests at the Pre-Seed, Seed, Series A stages.
- What sectors does Castle Island Ventures focus on?
- Castle Island Ventures focuses on Crypto & Web3.
- Where is Castle Island Ventures located?
- Castle Island Ventures is headquartered in Boston, US.
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