tBTC Bitcoin Bridge

A Decentralized, Permissionless Bitcoin Bridge to DeFi

Existing solutions that bridge Bitcoin to DeFi require users to send their Bitcoin to an intermediary, in exchange for an IOU token that represents the original asset. This centralized model requires you to trust a third party and is susceptible to censorship, threatening the premise of Bitcoin as sovereign, secure, permissionless digital asset.

In contrast, tBTC is a decentralized (and scalable) bridge between Bitcoin and DeFi. It provides Bitcoin holders secure and open access to the broader DeFi ecosystem, allowing you to unlock your Bitcoin’s value to borrow and lend, mint stablecoins, provide liquidity, and much more.

Honest Majority Assumption

Instead of centralized intermediaries, tBTC uses a randomly selected group of operators running nodes on the Threshold Network to secure deposited Bitcoin through threshold cryptography. tBTC requires a threshold majority agreement before operators can perform any action with your Bitcoin. By rotating the selection of operators bi-weekly, tBTC protects against any individual or group of operators colluding to fraudulently seize the underlying deposits. By relying on an honest-majority-assumption, we can calculate the likelihood any wallet comprised of a quorum of dishonest operators (for a deeper discussion of the probability calculations, see here).

Fees

tBTC fees are action-based (i.e. users incur a mint and redemption fee when using the bridge). Currently, the mint fee is 0% and the redemption fee is 0.2%. The bridge fees can be changed through governance.