# Welcome ## Summary * LeadFi Docs ### Overview * What is LeadFi * How LeadFi Works ### Using LeadFi * Getting Started * Mint leadBTC * Withdraw to BTC * Bridge Across Chains ### Product * Supported Wallets & Networks * Fees & Limits * Security & Custody (Cobo MPC) * Reserves & Transparency ### Support * FAQ * Help & Contacts ### Reference * Bitcoin Address Formats * Glossary # About Welcome! LeadFi brings native Bitcoin liquidity to EVM ecosystems via **leadBTC** — a 1:1 BTC-backed asset you can mint, bridge, and redeem back to the Bitcoin network. **Who is this for?** * Everyday users who want to put BTC to work in DeFi. * Institutions needing predictable flows and VIP service. * Anyone seeking clarity on security, custody, and reserves. > **Custody:** LeadFi uses **Cobo’s MPC wallet infrastructure** for operational and reserve custody controls. # What is LeadFi LeadFi is a user-friendly bridge that turns native BTC into **leadBTC**, an ERC-20 style token you can use across supported EVM chains. You can always redeem leadBTC back to native BTC. **Why it matters** * Put idle BTC to work in DeFi. * 1:1 relationship: 1 BTC ↔ 1 leadBTC (minus network & policy fees). * Simple UX: connect wallets, follow prompts, track status in-app. **Core actions** * **Mint**: Send BTC to the LeadFi reserve address (memo handled automatically in-app) → receive leadBTC. * **Bridge**: Move leadBTC between supported EVM networks. * **Withdraw**: Burn leadBTC on an EVM chain → receive native BTC. # How LeadFi Works **At a glance** 1. You initiate a mint in the app. Your Bitcoin wallet sends BTC to the LeadFi reserve address. The app includes a memo (OP\_RETURN) linking your EVM address to the deposit. 2. LeadFi verifies the BTC deposit on-chain and mints the same amount of **leadBTC** to your EVM address. 3. You can bridge leadBTC between chains (powered by LayerZero, via OFT). 4. When you withdraw, leadBTC is burned on EVM and an equivalent amount of BTC is released to your Bitcoin address. **Key principles** * **1:1 backing**: leadBTC is backed by reserves. See *Reserves & Transparency*. * **Non-custodial to you, institutional custody for reserves**: reserves are secured with **Cobo MPC**. * **No exchange transfers**: always use your self-custody wallet (don’t send directly from exchanges). # Getting Started ### What you need * A **Bitcoin wallet** (e.g., UniSat, OKX Wallet, Binance Web3) with BTC. * An **EVM wallet** (e.g., MetaMask, OKX Wallet, Binance Web3) with a small amount of native gas (ETH/BNB/etc.) for approvals and transactions. ### Basic flow 1. Open LeadFi and select an action (Mint / Withdraw / Bridge). 2. Connect your wallets in-app. 3. Follow the on-screen steps; the app handles memos and explorer links. 4. Track your transaction status on the confirmation screen and in the **Recent Activity** section. > **Tip:** For large amounts (≥ 10 BTC or equivalent), reach out to the VIP desk for preferential fees and priority processing. See *Help & Contacts*. # Mint leadBTC ### Steps 1. **Choose target network** (e.g., BNB Chain). 2. **Enter BTC amount.** The app will estimate Bitcoin network fee. 3. **Connect EVM wallet** (to receive leadBTC). 4. **Connect Bitcoin wallet** and confirm the transaction. The app includes the required memo automatically. 5. **Wait for confirmations.** Typical time: \~60 minutes depending on Bitcoin network conditions. ### Do's & Don'ts * ✅ Always mint from your **self-custody** Bitcoin wallet. * ❌ Do **not** send from an exchange deposit address. * ❌ Do **not** send directly to the reserve address outside the app flow (no memo, no mapping). ### After mint * You’ll see leadBTC in your EVM wallet on the selected network. * You can bridge it to other supported chains or use it in DeFi. # Withdraw to BTC ### Steps 1. **Select source network** where your leadBTC is held. 2. **Enter amount** to redeem. The app displays the withdrawal fee (policy-based) and estimates your net BTC. 3. **Connect EVM wallet** and approve if needed. 4. **Enter or connect your Bitcoin address** (the app validates mainnet vs testnet formats). 5. **Confirm withdrawal** and track the status. ### Timelines * On-chain confirmations + operational checks. Typical window: **\~30–60 minutes**, may vary with network congestion. * Large withdrawals may require **additional manual review** for safety. ### Address safety * **Mainnet** BTC addresses usually start with `bc1`, `1`, or `3`. * **Testnet** BTC addresses usually start with `tb1`, `m`, `n`, or `2`. * The app warns if your address format doesn't match the current environment. # Bridge Across Chains Move leadBTC between supported EVM networks (powered by LayerZero). ### Steps 1. Select **From** and **To** networks. 2. Enter the amount. The app estimates **native gas** required on the source chain. 3. Connect your EVM wallet and **switch to the source chain** when prompted. 4. Confirm the bridge transaction and wait a few minutes (typical: **5–15 minutes**). > **Note:** Bridge fees are paid in the **source chain’s native token** (ETH/BNB/etc.). Keep a small buffer for gas. # Supported Wallets & Networks ### Wallets * **Bitcoin**: UniSat, OKX Wallet, Binance Web3. * **EVM**: MetaMask, WalletConnect (mobile), OKX Wallet, Binance Web3. ### Networks * LeadFi supports multiple EVM networks for minting and bridging, and the Bitcoin network for settlement. * In test environments, addresses and explorers differ from mainnet (the app labels them clearly). > For the current list of supported networks, see the network selector inside the app. # Fees & Limits * **Mint** * **Minting service fee**: 1000sat (currently). * **Bitcoin network fee**: dynamic, displayed before you send. * **Withdraw** * **Withdrawal policy fee**: 3000sat (currently). * Net BTC = Amount − Fees. * **Bridge** * Paid in **source chain native gas** (ETH/BNB/etc.), estimated in-app. **Large flows & VIP** * For ≥ **10 BTC (or equivalent)** flows, contact the VIP desk for preferential fees and priority handling. > Fees can vary with network conditions. The app always shows the latest estimates before you confirm. # Security & Custody (Cobo MPC) Your safety is our priority. LeadFi uses a combination of operational controls and institutional custody. ### MPC with Cobo * LeadFi leverages **Cobo’s MPC wallet infrastructure** to secure operational and reserve keys. * **MPC (Multi-Party Computation)** means transaction approvals require multiple distributed key shards, reducing single-point-of-failure risk compared to single private keys. ### Operational safeguards * **Multi-party approvals** for sensitive actions. * **Cold storage majority**: the vast majority of reserves are stored offline with strict operational policies. * **Withdrawal delay & manual review** for large transactions. * **Principle of least privilege** for operational access. ### User self-custody * You retain control of your EVM and Bitcoin wallets. LeadFi never asks for your seed phrase or private keys. * Always verify you are interacting with the official LeadFi app. # Reserves & Transparency leadBTC is intended to be fully backed 1:1 by Bitcoin reserves. ### What we publish * **Canonical reserve addresses** for on-chain verification. * **Token contract addresses** on supported EVM networks. * **Explorer links** for both BTC and EVM transactions. > Always verify addresses inside the official app interface. Never trust addresses shared by third parties. ### How to verify (high level) 1. **BTC side**: View the reserve address on a public explorer (e.g., mempool.space) and check balances/transactions. 2. **EVM side**: View the leadBTC token contract on the chain’s block explorer and check total supply. 3. **Compare** outstanding leadBTC supply with reserves (adjusting for pending settlements). More detailed proofs (e.g., dashboards, audit summaries) will be announced in-app and on our official channels. # Contract Addresses ## Token Address **BNB Smart Chain:** **Ethereum:** ## Core Contract **CustodyManager:** [**https://bscscan.com/address/0xAA69709c0780ED5aA03f96D8CbD4C905861f4699**](https://bscscan.com/address/0xAA69709c0780ED5aA03f96D8CbD4C905861f4699) # FAQ **Is 1 BTC always equal to 1 leadBTC?**\ Yes, minting and redemption target a 1:1 relationship (minus applicable network/policy fees). **How long does minting take?**\ Typically \~60 minutes, depending on Bitcoin network congestion. **Can I bridge leadBTC between all supported chains?**\ Yes. Bridge fees are paid in the source chain’s native gas token. **Why was my large withdrawal delayed?**\ Large withdrawals may trigger additional manual review for security. **Can I mint by sending BTC directly to the reserve address from an exchange?**\ No. Always mint through the app with your self-custody wallet so the required memo is included. **My BTC address was rejected. Why?**\ If you’re on testnet, your address must look like a testnet address (`tb1`, `m`, `n`, or `2`). On mainnet, use `bc1`, `1`, or `3`. The app checks formats to prevent mistakes. # Bitcoin Address Formats * **Mainnet** * Bech32: `bc1...` (SegWit), `bc1p...` (Taproot) * Base58: `1...` (P2PKH), `3...` (P2SH) * **Testnet** * Bech32: `tb1...`, Taproot: `tb1p...` * Base58: `m...` / `n...` (P2PKH), `2...` (P2SH) > LeadFi validates that your address format matches the current environment (mainnet vs testnet) to reduce mistakes. # Glossary **leadBTC** — An ERC-20-style token representing BTC 1:1 on EVM networks.\ **MPC** — Multi-Party Computation, a method of splitting key material so multiple parties/shards must cooperate to sign.\ **OP\_RETURN** — A field in Bitcoin transactions used to store small pieces of data (LeadFi uses it to map your EVM address during mint).\ **OFT** — Omnichain Fungible Token; a cross-chain token pattern used with LayerZero for bridging.