Blowfish
Acquired6 known investors
Blowfish provides fraud detection and prevention APIs for Web3 wallets, identifying and blocking malicious transactions and decentralized applications across 10+ blockchain networks. The platform serves wallet providers and integrators with transaction security, dApp connection verification, and risk signal aggregation.
Also known as Blowfish.xyz · blowfishxyz
Investors · 6
Also in the syndicate · 3
Company profile
researched Aug 2026Blowfish (blowfish.xyz) developed firewall technology for web3 users, centered on a set of APIs that wallets, custodians and other integrators call before a user signs a transaction or message. The service simulates and scans the pending transaction, compares it against patterns observed in prior scams, and returns real-time warnings plus plain-language context about how the transaction would affect the user's wallet. Stated threat coverage includes phishing attempts and decentralized application DNS hijacking. At the time of its 2022 funding announcement the product was available on Solana, Ethereum and Polygon, with proceeds intended to extend coverage to additional chains.
Alongside the integrator-facing API, Blowfish shipped Blowfish Protect, a browser extension for Chrome, Brave, Arc and other Chromium-based browsers. The extension surfaces warnings about malicious websites and risky signing requests for users whose existing wallet does not embed Blowfish, which had previously been the only way to access the technology. The company also maintained public code, including a JavaScript/TypeScript library for using Blowfish blocklists locally, a transparent proxy for the Blowfish API, and forks of Solana, Metaplex and phishing-detection projects.
Founding story
A third-party profile dates the founding to 2022 and names CEO Fabio Berger, Oskar Paolini and two additional former 0x colleagues as founders. Press coverage describes a founding team of engineers drawn from companies including Meta, 0xLabs and MakerDAO. Co-founder Oskar Paolini was previously a DevOps engineer at 0x Labs, co-founder and CTO Kim Persson a senior software engineer at 0x Labs, and CEO Fabio Berger a senior engineer and engineering manager on 0x Labs' developer experience team.
Business model
Software-as-a-service: Blowfish licensed a security API to digital asset wallets and institutional custodians that embed its transaction screening into their signing flows, complemented by a free-standing consumer browser extension.
Sources describe a SaaS model selling security software to wallets and custodians; specific pricing or revenue figures are not disclosed in the material reviewed.
Traction
Phantom's CTO and co-founder stated in September 2022 that Blowfish had helped protect thousands of Phantom users from scams and fraud. A later third-party profile lists a workforce of roughly 14-21 employees and $23.8 million in total venture funding.
Latest developments
The most recent company-specific development in the sources is the reported November 2024 acquisition by Phantom. The GitHub organization shows repository updates through 2025 and 2026, including the blocklist library and an archived copy of the Blowfish website.
▸Full profile — market position, technology, go-to-market, geography, history, risks & controversies
Market position
Positioned as a web3 firewall and wallet-security vendor. Coverage from September 2022 grouped Blowfish with other on-chain firewall providers raising capital in the same week, notably Harpie, which raised $4.5 million for Ethereum wallet theft prevention with participation from Blowfish investor Dragonfly Capital.
Pre-signature simulation of transactions and messages with pattern matching against known scam behavior, delivered both as an API for wallet integrators and, unusually for the category, as a browser extension so users can retain their existing wallet while gaining the same protection.
Technology
Transaction simulation and scanning performed server-side via API: submitted transactions or messages are simulated and matched against patterns from previously observed scams, with results returned as risk warnings and human-readable descriptions of expected wallet impact. Supporting components include locally usable blocklists, a transparent API proxy, and forks of Solana program libraries, an Ethereum Rust library, a Solana data parser and a web3 phishing-domain detector.
Go-to-market
Distribution primarily through embedding in partner wallets, announced with a launch partnership with Solana wallet Phantom and later with Timeless Wallet, supplemented by direct-to-user distribution through a Chromium browser extension and open-source developer tooling.
Crypto wallet providers and institutional custodians integrating pre-signature transaction screening (e.g., Phantom, Timeless Wallet), plus end users of the Blowfish Protect browser extension who use wallets without native Blowfish support.
Geography
Sources place the company in Switzerland, with one profile specifying Zug; the same profile separately lists a Culver City, California address. The domain registrant is described as a Namecheap customer in Switzerland.
History
Blowfish emerged from stealth on 30 September 2022 with an $11.8 million round led by Paradigm and a partnership with Phantom. Over 2023 it added a partnership with Timeless Wallet and launched the Blowfish Protect browser extension. A third-party profile reports total funding of $23.8 million and an acquisition by Phantom in November 2024; the company's GitHub organization subsequently archived its website and frontend repositories, though several repositories show commit activity into 2025 and 2026.
Risks & controversies
No controversies are described in the reviewed sources. Data on the company is inconsistent across third-party aggregators: reported totals range from an $11.8 million round to $12.0 million and $23.8 million in cumulative funding, employee counts and headquarters differ between listings, and one aggregator profile mixes in an unrelated UK IT services firm of the same name.
Compiled by commissioned research from 5 cited public sources — announcements, filings, and press listed under research sources below.
Key figures
latest reportedCompany-reported or press-reported figures, each dated to when it was claimed — not independently audited.
Timeline · 5
launches, deals, and filingsAccording to a Startup Intros profile, Blowfish was acquired by Phantom, previously a major customer, in November 2024.
Blowfish announced a partnership with crypto wallet Timeless Wallet to integrate Blowfish's security checks into the wallet's transaction flow.
Blowfish released Blowfish Protect, a browser extension for Chrome, Brave, Arc and other Chromium-based browsers that warns users about malicious sites and risky transactions or messages before signing, making Blowfish's scanning available to users whose wallets have not integrated the API.
Blowfish announced an $11.8 million funding round led by Paradigm, with participation from Dragonfly Capital, Uniswap Labs Ventures, Hypersphere and 0xLabs. Proceeds were earmarked for team expansion, upgrading the API's fraud detection engine and adding support for new blockchains.
$11.8M source ↗
Phantom, a Solana wallet provider, integrated Blowfish; Phantom CTO and co-founder Francesco Agosti said Blowfish had helped protect thousands of Phantom users from malicious scams and fraud.
Dated company events from announcements, filings, and press; legal rows summarize public dockets and regulator releases.
In the news
▸Research sources · 5
primary sources listed
- Blowfish · GitHubgithub.com · web
5 public sources were cited for this profile; the first-party ones are listed here.
Frequently asked questions
- What does Blowfish do?
- Blowfish built a web3 firewall API that simulates and screens wallet transactions for scams; acquired by Phantom.
- Who are Blowfish's investors?
- Blowfish's investors include Dragonfly, Paradigm, Caffeinated Capital.