Castle Island Ventures leads $2.8 million pre-seed round for liquid vault startup RockSolid

Quick Take
- Castle Island Ventures is leading a $2.8 million pre-seed round into RockSolid, a liquid vaults startup that is emerging from stealth.
- Other notable backers include the Blockchain Builders Fund, GSR, Kindred Ventures, Rocket Pool, and the Stanford Blockchain Accelerator, among others.

Castle Island Ventures is leading a $2.8 million pre-seed round into RockSolid, an institutional-grade liquid vaults startup that is emerging from stealth. Other notable backers include the Blockchain Builders Fund, GSR, Kindred Ventures, Rocket Pool, and the Stanford Blockchain Accelerator, among others.
According to an announcement on Wednesday, RockSolid is also launching the "first and official" rETH vault for Rocket Pool, the decentralized Ethereum liquid staking protocol behind the rETH liquid staking token.
Rocket Pool is a decentralized staking protocol that enables users without 32 ETH to participate in Ethereum’s proof-of-stake security mechanism. The protocol issues the liquid staking token rETH, which enables holders to earn staking rewards while maintaining liquidity.
RockSolid’s first vault is a white-labelled, single-click rETH vault that is integrated directly into the Rocket Pool front-end and staking app, "offering seamless access to curated DeFi strategies and expanded opportunities for rETH holders," the team wrote.
"They are not building another experimental protocol. They are creating vaults that make it easy for anyone, from institutions to communities, to access DeFi strategies without the friction," Castle Island Ventures Founding Partner Nic Carter said.
The startup will use its pre-seed funding to expand its engineering, sales, marketing, and operations teams, according to the announcement. RockSolid also offers white-label vaults that enable protocols, institutions, wallets and digital asset treasuries (DATs) single-click access to DeFi.
Today, Rocket Pool is the third-largest decentralized staking protocol with over $2.7 billion in staked ETH. rETH typically trades higher than ETH, in part because its value increases relative to ETH over time as staking rewards accrue, reflecting the accumulated yield from validators in the Rocket Pool protocol.
Editor's note (Sept. 25 14:20 UTC): Clarifies that RockSolid is a liquid vault startup.
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