Castle Island Ventures

Alpen Labs is a startup focused on enhancing Bitcoin scalability through zero-knowledge technology. The company aims to create a comprehensive financial ecosystem that promotes privacy and programmability within Bitcoin. By developing an online platform, Alpen Labs seeks to foster broader adoption of cryptocurrency and expand global financial access. Its infrastructure empowers developers to build applications directly on this platform, facilitating an inclusive financial future for everyday users. Through its innovative approach, Alpen Labs is positioned to significantly contribute to the evolution of the cryptocurrency landscape.

CAT Labs specializes in cybersecurity and digital asset recovery solutions aimed at assisting governments in the fight against cryptocurrency-related crime. The company develops advanced tools designed to find, identify, and seize digital assets from a variety of sources, including smartphones, computers, servers, email accounts, and cloud storage. By providing these distinct capabilities, CAT Labs enables clients to enhance their digital asset protection and safeguard investors from scams, fraud, and hacking activities.

Hata is a regulated platform facilitating transactions between businesses and consumers, enabling access to cryptocurrencies using fiat currencies like the US Dollar and Malaysia Ringgit. It aims to provide safe and effortless access to cryptocurrency for all users through its commitment to customer service and regulatory compliance.

Yellow Card operates a cryptocurrency platform that enables individuals and businesses to buy, sell, and manage digital assets using local currencies and mobile money across Africa. The platform functions as a crypto exchange and payments solution, offering over-the-counter trading, merchant services, currency exchange, and crypto gift cards. It provides an on/off ramp for stablecoins such as USDT, USDC, and PYUSD through a payments API, supporting secure, cost-effective transfers and borderless transactions. The company serves customers in numerous African countries and has facilitated billions of dollars in transactions, reflecting its role in promoting financial inclusion and access to digital finance. Founded in 2016 and active in the market, Yellow Card aims to simplify crypto access for individuals and businesses through a scalable, local-currency-first approach.

Arch is a financial technology company that provides credit to asset owners through a liquid platform that manages all crypto assets in one place. The platform offers instant loans secured by crypto assets and non-fungible tokens, with over-collateralization and custody to prevent rehypothecation. It enables real-time asset tracking and aims to offer an efficient way to borrow against crypto and NFT holdings while consolidating asset management on a single interface.

SatLayer is a stealth-mode startup developing a modular security platform specifically designed for Bitcoin. Its core offering, Bitcoin Validated Service (BVS), aims to bolster the security of decentralized applications (dApps) and protocols within the cryptocurrency ecosystem.

Nirvana Labs provides cloud infrastructure specifically tailored for blockchain workloads, including Virtual Private Clouds and Virtual Machines. The company focuses on optimizing performance and reducing costs for various web3 applications while ensuring high availability and security. Its services support a range of blockchain companies, enhancing their operational efficiency and scalability.

Mountain Protocol is a financial technology company that operates a platform for issuing yield-bearing, regulated digital assets. Its flagship product, USDM, is a stablecoin backed by US Treasuries and custodied by Fidelity in a bankruptcy-remote setup, ensuring security and regulatory compliance. The platform aims to provide users with access to the risk-free rate, offering a seamless user experience and permissionless composability.

Monad is a proof-of-stake blockchain and decentralized computation platform that focuses on high performance and portability. It features a scalar architecture with pipelined execution, which allows for efficient transaction throughput. This innovative design enables developers to create complex decentralized applications (dApps) capable of processing a large volume of transactions quickly. By combining advanced technology with a user-friendly framework, Monad aims to enhance the overall functionality and scalability of decentralized applications in the blockchain ecosystem.

Station70 is a developer of a crypto security platform that provides scalable disaster recovery solutions designed to meet the security and regulatory requirements of businesses. The company offers trusted infrastructure to safeguard digital assets against interruptions and failures associated with wallet providers. Its platform focuses on delivering secure backup and recovery options for digital asset keys, ensuring that clients can effectively manage their assets while adhering to necessary security standards. Through its innovative approach, Station70 addresses the critical need for resilience in the evolving landscape of cryptocurrency security.

Build on Bitcoin is a hybrid Layer-2 network Bitcoin blockchain

Quantinium develops pioneering blockchain infrastructure, setting industry benchmarks in speed, security, and reliability. It incorporates decentralization, scalability, sustainability, and cybersecurity, facilitating Quantum Wi-Fi, a decentralized global Software-defined Wireless Network (SDWN). This technology transforms isolated Wi-Fi networks into interconnected ecosystems, enabling users to share surplus internet capacity.

Dynamic Labs is a developer of a wallet-based authentication and authorization platform that facilitates the adoption of non-fungible token wallets. The platform enables developers to implement wallet-based login, onboarding, and authentication processes, while also allowing for the addition and removal of blockchain networks. It provides tools for information collection and the structuring of access lists and gates, empowering developers to create customized authentication and user management solutions for their clients. By focusing on multi-chain capabilities, Dynamic Labs aims to streamline and enhance the user experience in digital identity management.

PYOR is a blockchain technology company that develops a web3 research platform aimed at accelerating global institutional participation. The company provides high-fidelity insights and data to establish a source of truth, offering a desktop analytics tool for deep dives into market sizing, growth estimation, and bespoke crypto research, delivering reliable digital data to businesses. With extensive expertise in crypto development, PYOR has contributed to the creation of several large Indian unicorns and brings broad experience with global blue-chip organisations, reinforcing its capability to translate complex web3 data into actionable intelligence for institutional clients.

CAT Labs specializes in cybersecurity and digital asset recovery solutions aimed at assisting governments in the fight against cryptocurrency-related crime. The company develops advanced tools designed to find, identify, and seize digital assets from a variety of sources, including smartphones, computers, servers, email accounts, and cloud storage. By providing these distinct capabilities, CAT Labs enables clients to enhance their digital asset protection and safeguard investors from scams, fraud, and hacking activities.

Arch is a financial technology company that provides credit to asset owners through a liquid platform that manages all crypto assets in one place. The platform offers instant loans secured by crypto assets and non-fungible tokens, with over-collateralization and custody to prevent rehypothecation. It enables real-time asset tracking and aims to offer an efficient way to borrow against crypto and NFT holdings while consolidating asset management on a single interface.

Alkimiya Protocol is a developer of an open-source, permissionless platform that focuses on creating financial instruments backed by actual hash power production. The protocol utilizes smart contracts to enable miners to sell their future production rewards for a predetermined amount. This innovation allows users to design and deploy hash power-backed financial instruments from any location, leveraging the latest web and mobile technologies to generate revenue. By facilitating a new way for miners to monetize their production, Alkimiya Protocol aims to enhance the financial landscape within the cryptocurrency sector.

Alpen Labs is a startup focused on enhancing Bitcoin scalability through zero-knowledge technology. The company aims to create a comprehensive financial ecosystem that promotes privacy and programmability within Bitcoin. By developing an online platform, Alpen Labs seeks to foster broader adoption of cryptocurrency and expand global financial access. Its infrastructure empowers developers to build applications directly on this platform, facilitating an inclusive financial future for everyday users. Through its innovative approach, Alpen Labs is positioned to significantly contribute to the evolution of the cryptocurrency landscape.

Sentiment is a decentralized finance company that specializes in facilitating chainless, undercollateralized borrowing. It has developed a permissionless DeFi protocol aimed at enhancing capital efficiency through innovative liquidity markets. The platform effectively mitigates solvency risk for lenders while maximizing capital efficiency for borrowers, all within a non-custodial and trustless framework. This approach enables clients to optimize the utility of their capital, making Sentiment a key player in the evolving landscape of decentralized finance.

Yellow Card operates a cryptocurrency platform that enables individuals and businesses to buy, sell, and manage digital assets using local currencies and mobile money across Africa. The platform functions as a crypto exchange and payments solution, offering over-the-counter trading, merchant services, currency exchange, and crypto gift cards. It provides an on/off ramp for stablecoins such as USDT, USDC, and PYUSD through a payments API, supporting secure, cost-effective transfers and borderless transactions. The company serves customers in numerous African countries and has facilitated billions of dollars in transactions, reflecting its role in promoting financial inclusion and access to digital finance. Founded in 2016 and active in the market, Yellow Card aims to simplify crypto access for individuals and businesses through a scalable, local-currency-first approach.

Founded in 2021, Evaluate.xyz is a platform based in Cambridge, Massachusetts that enables users to buy, sell, and analyze non-fungible tokens (NFTs). It provides tools for tracking and discovering NFTs, facilitating secure real-time trading with live chat.

Kinetic is a company currently operating in stealth mode, focusing on the development of a multi-chain NFT aggregator and trading platform tailored for the cryptocurrency market. Its platform aims to enhance the trading experience by consolidating cross-market visibility, allowing users to access a wide range of NFT transactions. Additionally, Kinetic provides personalized data feeds and predictive insights, which help users make informed decisions and achieve clarity in their trading activities.

Dynamic Labs is a developer of a wallet-based authentication and authorization platform that facilitates the adoption of non-fungible token wallets. The platform enables developers to implement wallet-based login, onboarding, and authentication processes, while also allowing for the addition and removal of blockchain networks. It provides tools for information collection and the structuring of access lists and gates, empowering developers to create customized authentication and user management solutions for their clients. By focusing on multi-chain capabilities, Dynamic Labs aims to streamline and enhance the user experience in digital identity management.

Try Your Best is a blockchain technology company that develops an online play-to-earn portal. The platform is designed to reward user engagement within a sustainable Web3 ecosystem, offering an energy-efficient experience where participation earns rewards and perks for users and their communities.

Try Your Best is a blockchain technology company that develops an online play-to-earn portal. The platform is designed to reward user engagement within a sustainable Web3 ecosystem, offering an energy-efficient experience where participation earns rewards and perks for users and their communities.

Eaglebrook Advisors is a cryptocurrency-focused investment firm that specializes in providing financial advisors with access to bitcoin through its proprietary asset management platform. The firm offers a range of services designed to facilitate the management of digital investments, including portfolio integration, institutional custody, tax optimization, and liquidation strategies. By prioritizing security and compliance, Eaglebrook Advisors aims to simplify the investment process for financial advisors, enabling them to effectively manage and optimize their clients' cryptocurrency assets.

Mint Songs is a prominent music NFT marketplace that focuses on enhancing the relationship between music artists and their fans. By utilizing non-fungible token technology, the company creates a platform where music enthusiasts can buy, sell, and trade music-related NFTs. This innovative approach not only facilitates transactions but also fosters the development of web3 communities, allowing artists to engage more deeply with their audience. Through its services, Mint Songs aims to empower artists and enrich the overall music experience for fans.

Yellow Card operates a cryptocurrency platform that enables individuals and businesses to buy, sell, and manage digital assets using local currencies and mobile money across Africa. The platform functions as a crypto exchange and payments solution, offering over-the-counter trading, merchant services, currency exchange, and crypto gift cards. It provides an on/off ramp for stablecoins such as USDT, USDC, and PYUSD through a payments API, supporting secure, cost-effective transfers and borderless transactions. The company serves customers in numerous African countries and has facilitated billions of dollars in transactions, reflecting its role in promoting financial inclusion and access to digital finance. Founded in 2016 and active in the market, Yellow Card aims to simplify crypto access for individuals and businesses through a scalable, local-currency-first approach.

Pintu is a cryptocurrency platform based in Jakarta, Indonesia, established in 2020. The company offers a mobile application that facilitates the buying, selling, and management of Bitcoin and other blockchain-based assets. Its platform provides users with a convenient way to access various financial services, allowing them to engage with the cryptocurrency market easily and securely. By streamlining the process of managing digital assets, Pintu aims to support the transition towards a more open financial system for its users.

Alkimiya Protocol is a developer of an open-source, permissionless platform that focuses on creating financial instruments backed by actual hash power production. The protocol utilizes smart contracts to enable miners to sell their future production rewards for a predetermined amount. This innovation allows users to design and deploy hash power-backed financial instruments from any location, leveraging the latest web and mobile technologies to generate revenue. By facilitating a new way for miners to monetize their production, Alkimiya Protocol aims to enhance the financial landscape within the cryptocurrency sector.

Founded in New York in 2018 by Anton Katz and Ethan Feldman, Talos is an institutional technology infrastructure provider that facilitates a comprehensive trading lifecycle for crypto ecosystem participants. It offers prime brokerage services, supporting spot, futures, and foreign exchange markets with institutional-grade technology.

Pintu is a cryptocurrency platform based in Jakarta, Indonesia, established in 2020. The company offers a mobile application that facilitates the buying, selling, and management of Bitcoin and other blockchain-based assets. Its platform provides users with a convenient way to access various financial services, allowing them to engage with the cryptocurrency market easily and securely. By streamlining the process of managing digital assets, Pintu aims to support the transition towards a more open financial system for its users.

Founded in 2017, Coin Metrics provides comprehensive crypto financial intelligence. It offers network data, market data, indexes, and risk management solutions to institutions, empowering them with transparent and actionable insights for informed decision-making.

Founded in 2021, Evaluate.xyz is a platform based in Cambridge, Massachusetts that enables users to buy, sell, and analyze non-fungible tokens (NFTs). It provides tools for tracking and discovering NFTs, facilitating secure real-time trading with live chat.

River Financial Inc. is a financial technology company based in San Francisco, California, founded in 2019 by Alexander Leishman and Andrew Benson. The company specializes in providing a platform for individuals and institutions to buy, manage, and sell bitcoin. Its flagship product is a Bitcoin brokerage designed for sophisticated retail investors, offering a high-touch service that prioritizes security and client experience. River Financial's platform includes tools for investment performance, such as cost basis tracking, catering to the needs of its clients in the evolving cryptocurrency market.

DFX Finance is a decentralized finance exchange protocol on the Ethereum blockchain that enables the trading of fiat-backed stablecoins. It uses a tuned bonding curve and real-world price feeds to provide a structured, decentralized trading experience for stablecoins such as USDC, CADC, EURS, and XSGD, supporting a broad range of blockchain-powered DeFi applications.

Valiu Inc. is a fintech company based in Bogotá, Colombia, specializing in electronic fund transfer services specifically for the Venezuelan market. Founded in 2018 by Simon Chamorro and Alberto Niego, Valiu has developed a mobile application that facilitates borderless financial services. This platform enables users to save, send, and receive money conveniently, regardless of their socioeconomic status or the capabilities of their mobile devices. By leveraging a blockchain-based remittance system, Valiu allows users to manage their finances without the reliance on traditional banking institutions, thereby providing accessible financial solutions for Venezuelans, including migrants and their families.

Notabene, Inc. is a New York-based company founded in 2020 that specializes in developing a software as a service (SaaS) platform for crypto compliance tailored for the financial industry. The company focuses on helping financial institutions adhere to emerging global regulations concerning cryptocurrency transactions, specifically addressing the complexities of the Travel Rule. Notabene offers a unified API and dashboard designed to assist compliance officers in managing risk associated with both Travel Rule and non-custodial transactions. By providing access to a broad network of crypto businesses, Notabene simplifies the compliance process, enhances transaction confidence, and ultimately supports its clients in increasing their transaction volumes and business growth.

Founded in New York in 2018 by Anton Katz and Ethan Feldman, Talos is an institutional technology infrastructure provider that facilitates a comprehensive trading lifecycle for crypto ecosystem participants. It offers prime brokerage services, supporting spot, futures, and foreign exchange markets with institutional-grade technology.

BlockFi, Inc. is a financial services firm that specializes in providing wealth management products for cryptocurrency investors. Founded in 2017 and headquartered in New York, BlockFi offers various services, including interest-bearing accounts for Bitcoin, Ether, and Gemini Dollar, as well as USD loans secured by clients' crypto assets. The company allows clients to trade cryptocurrency pairs and provides tailored lending solutions for both individual and institutional clients. By facilitating liquidity for blockchain asset holders, BlockFi aims to enhance transparency and efficiency in digital financial markets. The organization employs a robust infrastructure that integrates with multiple blockchains, positioning itself to adapt and expand its product offerings in response to the evolving needs of its users.

River Financial Inc. is a financial technology company based in San Francisco, California, founded in 2019 by Alexander Leishman and Andrew Benson. The company specializes in providing a platform for individuals and institutions to buy, manage, and sell bitcoin. Its flagship product is a Bitcoin brokerage designed for sophisticated retail investors, offering a high-touch service that prioritizes security and client experience. River Financial's platform includes tools for investment performance, such as cost basis tracking, catering to the needs of its clients in the evolving cryptocurrency market.

Founded in 2017, Coin Metrics provides comprehensive crypto financial intelligence. It offers network data, market data, indexes, and risk management solutions to institutions, empowering them with transparent and actionable insights for informed decision-making.

Zabo is a startup focused on providing financial companies with a comprehensive platform to connect and manage cryptocurrency accounts. Utilizing an API-based application, Zabo enables seamless integration of cryptocurrency accounts into existing applications with minimal coding. This innovative solution offers clients the functionality to buy, sell, and transfer cryptocurrencies while also providing support for hardware wallet integration. By allowing financial institutions to offer their customers a consolidated view of their crypto investments, Zabo enhances the user experience in managing digital assets.

BlockFi, Inc. is a financial services firm that specializes in providing wealth management products for cryptocurrency investors. Founded in 2017 and headquartered in New York, BlockFi offers various services, including interest-bearing accounts for Bitcoin, Ether, and Gemini Dollar, as well as USD loans secured by clients' crypto assets. The company allows clients to trade cryptocurrency pairs and provides tailored lending solutions for both individual and institutional clients. By facilitating liquidity for blockchain asset holders, BlockFi aims to enhance transparency and efficiency in digital financial markets. The organization employs a robust infrastructure that integrates with multiple blockchains, positioning itself to adapt and expand its product offerings in response to the evolving needs of its users.

ZenLedger develops software solutions for cryptocurrency tax management. It offers ZenLedger, a tool that enables users to import cryptocurrency transactions, calculate gains and income, and auto-fill tax forms. Its platform produces profit/loss statements and prepares various tax reports.

Flipside Crypto, Inc. is a Boston-based company founded in 2017 that specializes in providing analytics and business intelligence for blockchain organizations. The company offers a range of services, including cryptocurrency management, digital walleting, custody services, and portfolio dashboards aimed at investors. Flipside Crypto is known for its suite of analytics tools that deliver insights into user behaviors, developer activities, and financial metrics, including the Fundamental Crypto Asset Score (FCAS), which measures the health of cryptocurrency projects. The company collaborates with various partners to distribute its analytics, enhancing the visibility and understanding of cryptocurrency markets. Flipside Crypto is supported by notable investors, including Coinbase Ventures and True Ventures.

Founded in 2017, Coin Metrics provides comprehensive crypto financial intelligence. It offers network data, market data, indexes, and risk management solutions to institutions, empowering them with transparent and actionable insights for informed decision-making.

Flipside Crypto, Inc. is a Boston-based company founded in 2017 that specializes in providing analytics and business intelligence for blockchain organizations. The company offers a range of services, including cryptocurrency management, digital walleting, custody services, and portfolio dashboards aimed at investors. Flipside Crypto is known for its suite of analytics tools that deliver insights into user behaviors, developer activities, and financial metrics, including the Fundamental Crypto Asset Score (FCAS), which measures the health of cryptocurrency projects. The company collaborates with various partners to distribute its analytics, enhancing the visibility and understanding of cryptocurrency markets. Flipside Crypto is supported by notable investors, including Coinbase Ventures and True Ventures.

ZenLedger develops software solutions for cryptocurrency tax management. It offers ZenLedger, a tool that enables users to import cryptocurrency transactions, calculate gains and income, and auto-fill tax forms. Its platform produces profit/loss statements and prepares various tax reports.

Beam is a payment service that uses stablecoins to help people send money globally faster and cheaper.

Nirvana Labs provides cloud infrastructure specifically tailored for blockchain workloads, including Virtual Private Clouds and Virtual Machines. The company focuses on optimizing performance and reducing costs for various web3 applications while ensuring high availability and security. Its services support a range of blockchain companies, enhancing their operational efficiency and scalability.