bUSD Technical Spec

What is bUSD

bUSD is Bound's native stablecoin on Bitcoin - a Runes-based token backed 1:1 by other stablecoins. It serves as the settlement layer for all Bound structured products: loans, options, and escrow all settle in bUSD.

Role in the stack

• Loans - borrowed funds are denominated in bUSD

• Options - collateral and settlement use bUSD

• Escrow - all structured product settlement goes through bUSD

• Integration - other Bitcoin-native protocols can integrate bUSD as a stable settlement layer

Mint & redeem

bUSD is live with mint and redeem functionality.

Redeem

To redeem bUSD back to a stablecoin on EVM:

1. Send bUSD from your Bitcoin Bound wallet to Bound's hot wallet

2. The Bitcoin transaction embeds your EVM address and the target stablecoin ID in an OP_15 script

3. Bound reads the script and sends the corresponding stablecoin to your EVM address

Backing assets

bUSD is backed 1:1 by USDC and USDT, held in Ethereum multisig wallets:

Wallet	Address
ETH available reserves	0x1c51243C0aCFA2fBB2E06bfc2b9066C96Ff6d604
ETH offline reserves	0x00DA6e7A5Cd24bC1a79D0175fFB5724f8524F62f

Amounts exceeding $100,000 in the available reserves wallet are automatically swept to offline reserves.

Proof of reserves

bUSD circulating supply and backing can be verified on-chain at any time.

Circulating supply

Circulating bUSD = Total Supply − BTC available reserves − BTC offline reserves

Wallet	Address
BTC available reserves	bc1pkg6r6s0yevd465utaumyj5qf3dwgchzx83w4hlje776hk4qc9zus8dvn38
BTC offline reserves	bc1phr6t5mw4d58mqu9nd0gp9c9hfxe60wksdg5dxn330l75ucnpc56qatke8a

Backing USD

Backing USD = ETH available reserves + ETH offline reserves

Tracking redeem requests

Each redeem transaction embeds the user's EVM address on-chain in the Bitcoin script. You can verify any request by matching the Bitcoin transaction from the Bound wallet address with the EVM address in the redeem script.