About
Unbound Security was an Israel-based pioneer in cryptographic key-management and secure multi-party computation (MPC). Coinbase acquired Unbound Security in late 2021 to bolster its institutional custody, wallet and key-management technology. (Note: Unbound was acquired by Coinbase, not PayPal.)
Key products
- Founded
- 2014
- HQ
- Petah Tikva, Israel
- Stage
- Acquired
- Funding
- Acquired by Coinbase (2021)
Related companies
Casa
Self-custody multisig for Bitcoin, Ethereum and stablecoins
Casa is a self-custody security company (founded 2018) offering collaborative multisig vaults that distribute keys across a user's phone, hardware wallets and a Casa-held recovery key, so Casa never controls funds unilaterally. It supports Bitcoin, Ethereum and stablecoins and provides inheritance planning and key health checks, targeting individuals seeking sovereign yet resilient custody.
Cobo
Custody and wallet-as-a-service platform
Cobo provides full-suite stablecoin payment operations combining MPC custody, payment APIs and Wallet-as-a-Service across 80+ chains. It launched a stablecoin payment solution for cross-border business and integrated Plasma early, positioning as a qualified custodian and orchestration layer for stablecoin treasury and payments.
Coinbase
Largest US crypto exchange and USDC co-issuer
Coinbase is the largest US-listed crypto exchange and a primary stablecoin trading venue. It co-founded USDC with Circle via the Centre consortium and earns a share of USDC reserve revenue, while operating Base (its L2), Coinbase Wallet, custody and on/off-ramp services. In 2026 it is positioning around stablecoins, Base, and an 'everything exchange' strategy.
Curv
MPC-based digital asset security (acquired by PayPal)
Curv was an Israel-based provider of cloud-based, software-only digital-asset security infrastructure powered by multi-party computation (MPC), eliminating single points of failure by distributing key shares. PayPal acquired Curv in 2021 for under $200M to provide a security layer for its crypto operations and cross-border movement of digital assets.
DFNS
Wallet-as-a-service and key management API
Dfns is a wallet infrastructure and key-management platform offering API-driven MPC wallets, policy enforcement and HSM-backed key security, positioned as a core banking platform for digital assets. Clients include Circle, MoonPay, Broadridge and banks; it processed $26B+ of digital assets in 2025.
Fireblocks
MPC-based digital asset custody and transfer platform
Fireblocks is the most widely deployed institutional wallet and custody infrastructure provider, using MPC-CMP key management and a hardware-isolated transaction security layer. Its Fireblocks Network connects 2,000+ exchanges, banks, market makers and treasuries for direct settlement, and it is a leading rail for institutional stablecoin movement. Regulated custody workflows route through partner trusts and NYDFS-licensed subsidiaries.