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Portfolio

Castle Island Ventures

A closer look at the companies associated with this firm. Verified team members can update the portfolio after signing in.

Portfolio

Castle Island Ventures portfolio

This is the portfolio currently shown on the public firm page.

22 activeBack to firm page
Erebor BankListed
erebor.comfintech_payments
AlkimiyaListed
alkimiya.iocrypto_web3

Alkimiya is a market protocol for trading blockspace and fundamental metrics. It offers predictive markets and total supply forecasts for USDC, allowing users to manage and monito…

Alpen LabsListed
alpenlabs.iofintech_payments

Alpen Labs is building Bitcoin's future by enabling direct programmability of Bitcoin through zero-knowledge proofs, facilitating secure trading, borrowing, and the creation of fi…

AndrenaListed
andrena.comenterprise_software

Andrena provides high-speed Internet services starting at $30 per month, focusing on affordability and simplicity for residents and businesses. Their service includes plans up to…

ArcadeListed
arcade.softwaremarketing_adtech

Arcade is a platform that enables users to create interactive product demos and storytelling experiences quickly and easily. With features like a Creator Studio for on-brand visua…

Arch LendingListed
archlending.comcrypto_web3

Arch Lending provides secure and instant Bitcoin and crypto-backed loans, allowing users to unlock liquidity without selling their digital assets.

Asymmetry FinanceListed
asymmetry.financecrypto_web3

Asymmetry Finance is focused on providing innovative financial products such as stablecoins and structured products for liquid staking and restaking, aiming to supercharge yield s…

AtriumListed
atrium.commanufacturing_industrial

Atrium Windows & Doors is a leading manufacturer of high-quality vinyl windows and patio doors, committed to providing exceptional products and customer service since 1946.

AttestivListed
attestiv.comsecurity_cyber

Attestiv provides a cloud-scale platform to ensure the authenticity and validity of digital assets utilizing patented AI technology, addressing the challenges of fake and AI-gener…

Babylon LabsListed
babylonlabs.iocrypto_web3

Babylon Labs focuses on Bitcoin staking and decentralized finance (DeFi) solutions, providing institutional staking services and developing protocols for enhancing Bitcoin's utili…

BeamListed
No domain yetenterprise_software

Beam is a company that offers a comprehensive platform for construction project management, integrating tools for estimating, project management, and financial management. Their s…

Project ElevenListed
projecteleven.xyzsecurity_cyber

Project Eleven is an applied lab of builders and technologists at the intersection of quantum computing and cryptography, focusing on securing digital assets for the post-quantum…

RockSolidListed
rocksolid.ioenterprise_software

Rocksolid Solutions LLC is a supply chain solutions consultancy company that helps manufacturing companies improve processes, reduce waste and unlock working capital. Unlike large…

TalosListed
No domain yetfintech_payments

Talos provides institutional-grade technology and data that supports the full digital asset investment lifecycle, including liquidity sourcing, price discovery, trading, settlemen…

Crusoe EnergyListed
crusoeenergy.comdeveloper_tools_infra

Crusoe Energy provides renewable-powered AI infrastructure, focusing on managed inference services for AI workloads.

MoonpayListed
moonpay.comfintech_payments

MoonPay simplifies access to buy, sell, and trade cryptocurrencies using everyday payment methods like cards, Apple Pay, PayPal, and Venmo. With nearly 30 million customers and pa…

Pear ProtocolListed
pear.gardencrypto_web3

Pear Protocol is a decentralized trading platform that specializes in pair trading, allowing users to go long and short on multiple tokens with leverage. It features advanced trad…

Birdai LabsListed
birdai.xyzcrypto_web3

Birdai Labs builds neutral infrastructure for onchain execution quality, measuring where value leaks between an order and its fill, proving it against the chain, and aiming to ret…

CyclopsListed
No domain yetcrypto_web3

Cyclops Inc. provides all-in-one crypto and stablecoin solutions for payments companies, offering services like receiving payments, settlement, conversion, and payouts. The compan…

ValinorListed
valinor.aiaerospace_defense

Valinor is a new type of defense and government tech company focused on solving the problems others don’t. Our unique model of centralized go-to-market and decentralized engineeri…

XFXListed
xfx.comgaming

Creators of mind blowing graphics cards. XFX was founded in 2001 with a commitment to PC gaming and that commitment is still honored today. The brand name was derived from the exp…

Birch HillListed
birchhill.comfintech_payments

Birch Hill Equity Partners is a Canadian private equity firm focused on mid-market investments, with a history of active portfolio growth and strategic acquisitions across various…