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Bitcoin Venture Capital · 2017-Present

Castle Island Ventures

Nic Carter and Matt Walsh.

Fund Size

$250M+ across multiple funds.

Thesis

Bitcoin infrastructure, stablecoins, and financial plumbing. Castle Island's focus is on the companies building the connective tissue between Bitcoin, digital assets, and the traditional financial system, the picks-and-shovels of the industry. They bring a deeply analytical, data-driven approach rooted in their Fidelity backgrounds.

Portfolio

Blockstream, River, Voltage, NYDIG, Coin Metrics, Casa, Bitwise, Talos, MoonPay, Flipside Crypto, Matrixport, and other infrastructure companies across the ecosystem.

Why It Matters

Carter and Walsh's Fidelity pedigree gives them access to institutional LPs, while their deep technical understanding of Bitcoin makes them trusted partners for founders. Their research output (particularly Carter's) has shaped how allocators think about the space.

Companies on this list they backed

Blockstream, NYDIG, River, Arch, BlockFi, Casa

Cite & share

Early Riders. “A Brief History of Bitcoin Venture Capital: Castle Island Ventures.” https://earlyriders.com/top50/vc/castle-island-ventures/

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