Summary
Following the successful migration of BTC.b to Lombard’s security model, LlamaRisk supports onboarding BTC.b to the Aave V3 Core Instance. BTC.b on Ethereum is currently backed by approximately $13M in DEX liquidity, entirely protocol-supplied by the Lombard team, which mitigates the risk of abrupt liquidity removals, as it is not subject to the typical flight dynamics of third-party LPs. While the current circulating supply stands at ~32 BTC ($2.1M), this is consistent with the asset’s recent launch on Ethereum and is expected to grow as the ecosystem matures and bridging activity increases.
BTC.b on Ethereum benefits from robust administrative safeguards. Contract upgrades are subject to a 1-day timelock enforced via LombardTimeLock, with the executor role controlled by Lombard’s 3/5 Safe multisig. The protocol maintains an active bug bounty program, and the most recent audits have not surfaced any critical or high-severity findings. On the fee side, BTC.b carries a modest mint fee of 29 satoshis (~$0.02) and a flat redemption fee of 10,000 satoshis (~$6.50) for withdrawals to native BTC, both of which are negligible relative to typical transaction sizes. Taken together, these factors suggest that BTC.b presents a manageable risk profile for integration into Aave. However, continued monitoring of supply growth and liquidity depth will be prudent as the asset establishes itself on Ethereum.
1. Asset Fundamental Characteristics
1.1 Asset
According to the Aave Asset Class Allowlist (AAcA), Cross-chain Bitcoin (BTC.b) is classified as a bridged BTC wrapper, and assets of this category have already been approved for use on Aave. BTC.b is an ERC20 token on Ethereum, Avalanche, Katana, MegaETH, Monad, and Stable, backed 1:1 by BTC. It was established in 2022 by Ava Labs and later acquired by Lombard Finance in October 2025 to expand its product suite and offer a non-yield-bearing Bitcoin asset alongside its yield-bearing LBTC counterpart.
At present, approximately 3,566 BTC.b of the total 3,632 (~$238M) supply resides on Avalanche, while only 32.43 BTC.b ($2.1M) is issued on Ethereum. This highlights that the vast majority of supply remains on Avalanche, with Ethereum representing a relatively small and early-stage share of total circulation.
1.2 Architecture
BTC.b on Ethereum is built on Lombard Finance’s NativeLBTC infrastructure. The AssetRouter contract acts as the canonical entry point for deposits, redemptions, and payload routing. It maintains per-token configuration, including redemption fees (redeemFee+ toNativeCommission), mint fee caps, and oracle references. For cross-chain transfers, BridgeV2 enforces a burn-and-mint bridging logic: outbound transfers burn tokens and dispatch a message via the Mailbox (a GMP abstraction layer), while inbound messages are finalized as mints only after they are accepted.
Source: Lombard Finance, February 23, 2026
Lombard’s trust architecture rests on three components.
- The Consortium contract is an epoch-based weighted multi-signature verifier: it maintains a validator set per epoch, where each validator has an address and a weight. When a proof-based mint is submitted, the contract decodes an array of ECDSA signatures, sums the weights of matching signers, and reverts if the total weight falls below the threshold. Validator set rotations are themselves consortium-attested;
setNextValidatorSet requires a valid proof from the current epoch’s validators, ensuring the quorum cannot be unilaterally changed. The Lombard Security Consortium consists of the following 15 independent digital asset institutions.
Source: Lombard Finance, February 23, 2026
- The Bascule drawbridge provides independent verification: when enabled, every proof-based mint must also pass
validateWithdrawal(depositID, amount), confirming the Bascule has independently observed the corresponding Bitcoin deposit. Currently, this address is set to null, meaning the Bascule check is disabled.
- Cubist CubeSigner underpins the key management layer, providing HSM-backed signing where key material is never exposed to operators and signing is constrained by policy.
Fee
The fee structure operates across multiple layers. For minting, there is a flat fee cap (maximumMintCommission) stored per-token in the AssetRouter’s TokenConfig, currently set to 29 satoshis (~$0.02). For redemptions (burning BTC.b to receive BTC), the AssetRouter deducts a flat redeemFee of 0 (in satoshis) from the burn amount before processing. An additional toNativeCommission of 10,000 satoshis ($6.5) is applied through the Validation.redeemFee calculation during redemption to BTC. The mint fee cap is adjustable by the operator, currently an EOA, while redemption fees (redeemFee and toNativeCommission) are governed by the AssetRouter’s admin, the LombardTimeLock contract.
1.3 Tokenomics
The total supply of BTC.b is variable and expands or contracts based on user-driven bridging of native BTC. On Ethereum, the circulating supply currently stands at 30.45 BTC.b, held across just 29 unique addresses, indicating a still-nascent holder base.
In contrast, the majority of BTC.b supply resides on Avalanche, with approximately 3,566 BTC.b outstanding. Smaller allocations exist on other networks, including Monad (23.42), MegaETH (15.37), Stable (10.78), and Katana (7.82), bringing the aggregate cross-chain supply to ~3,659 BTC.b.
1.3.1 Token Holder Concentration
Source: BTC.b Top 100 Token Holders, Etherscan, February 23, 2026
The top 3 holders of BTC.b are:
The top three holders collectively control 99.98% of BTC.b’s total supply on Ethereum, reflecting a highly concentrated ownership structure. Meanwhile, approximately 90% of the circulating supply is held on DEXs, supporting deep on-chain liquidity and facilitating efficient trading.
2. Market Risk
2.1 Liquidity
Source: LlamaRisk, February 23, 2026
Users can swap 187 BTC.b for $12.27M USDC within a price impact of 7.5%.
2.1.1 Liquidity Venue Concentration
Source: LlamaRisk, February 23, 2026
On-chain liquidity for BTC.b on Ethereum is concentrated across two recently deployed pools: Uniswap V4 BTC.b/WBTC ($10.97M TVL) and Curve BTC.b/cbBTC ($2.62M TVL). Both of these pools were seeded with liquidity this month, with the majority added on February 9, 2026. The majority of this BTC.b liquidity is sell-side, totaling ~180 BTC ($11.9M), consistent with the price slippage chart, which shows a cliff beyond $12M in trade size.
2.1.2 DEX LP Concentration
BTC.b liquidity on Ethereum is highly concentrated, with the Lombard team accounting for nearly 100% of the DEX liquidity across pools. This reflects a near-exclusive reliance on a single liquidity provider at the current stage of market development. Below is the breakdown (as of February 23, 2026):
- Uniswap V4 BTC.b/WBTC: Lombard BTC Vault is the top supplier, with a near-100 % share of the pool’s liquidity.
- Curve BTC.b/cbBTC: Lombard BTC Vault is the top supplier with nearly 100% share of the pool’s liquidity.
2.2 Volatility
Source: GeckoTerminal, February 23, 2026
BTC.b has consistently maintained its 1:1 peg to BTC across secondary markets and is currently trading at a modest 26-basis-point (bps) premium.
2.3 Exchanges
BTC.b is exclusively traded on DEXs and is not currently listed on any centralized exchange.
2.4 Growth
Source: LlamaRisk, February 23, 2026
BTC.b, following its migration and deployment on Ethereum, has seen upward growth since late October 2025. As of February 23, the circulating supply on Ethereum stands at 32.43 BTC.b, representing a ~24% drawdown from its early-February peak. A closer inspection of the supply chart indicates that these changes were largely driven by a small number of sizable single-mint-and-burn transactions, rather than gradual organic inflows or outflows, suggesting that activity on Ethereum is still in the early stages and continues to scale post-deployment.
3. Technological Risk
The BTC.b technological risk on Ethereum, including smart contract risk, bug bounty program, and dependency risk, remains unchanged since our BTC.b MegaETH onboarding review and is excluded here for brevity, as no new contracts have been deployed, and the underlying architecture remains identical.
4. Counterparty Risk
4.1 Governance and Regulatory Risk
The operational setup has evolved since our previous review of Lombard Finance. A Cayman foundation has been established to act as the steward of the Lombard Protocol, oversee initiatives, and own Lombard Finance Ltd., a Cayman limited entity and the developer of the Lombard Protocol. The company acts as operator of the DAO and DAO-related activities for the Lombard Protocol and its products.
Lombard’s Terms of Service set out the services rendered by Lombard Finance Ltd., namely providing access to and use of the Lombard Finance website and/or the website-hosted user interface available at lombard.finance (the “App”), as well as certain features contained on the Website and in the App. Lombard states that it is not acting as a broker, financial institution, or creditor, and that the Services are provided only as an administrative platform. Lombard Finance is not authorised or regulated by the UK Financial Conduct Authority. Protections provided by the UK regulatory system will not be available to users when using Lombard.
As per our review, Lombard’s Terms are drafted to permit Lombard to implement and enforce mixer-related compliance controls based solely on risk signals, without requiring proof that a user “actually used” a mixer. The broad Prohibited Uses definition gives Lombard ample contractual cover to treat mixer exposure as an AML/sanctions risk-management measure. Importantly, there is a practical limitation to such measures: Lombard can only police what it controls (the front-end and Lombard-run features), not the underlying on-chain Protocol state.
The Lombard team relies on legal counsel across various jurisdictions (the US, Europe, and Singapore), which has advised on BTC.b’s legal implications and regulatory compliance. According to the team, because BTC.b is simply a wrapped asset, no regulatory blockers have arisen.
While BTC.b is offered as a tokenised representation of native Bitcoin, certain structural features carry distinct regulatory implications, particularly in the US and the Cayman Islands. The assumptions below are set out for the purpose of testing the asset’s regulatory exposure.
In the US, native BTC is widely accepted as a commodity under CFTC jurisdiction. However, viewed through a conservative regulatory lens, BTC.b may be seen as having an identifiable issuer (Lombard), a consortium-based minting apparatus, and cross-chain bridging infrastructure that, collectively, may satisfy the “investment contract” prong of the Howey test. A key mitigating factor is that BTC.b does not generate yield, which weakens the “expectation of profits from the efforts of others” element.
In the same vein, BTC.b’s permissionless minting and redemption mechanism—where users deposit native BTC and receive BTC.b tokens across multiple chains—may constitute a money transmission service under FinCEN’s definitions.
In the Cayman Islands, BTC.b, as a 1:1 wrapper of a commodity with no yield or governance rights, is unlikely to qualify as a security. However, if the wrapper were recharacterised as a derivative of BTC (because it derives its value from the underlying), the SIB Act definition could apply. The 2026 amendments clarifying that tokenised fund interests do not require VASP licensing may provide some analogical support for non-securities treatment.
Strong mitigating factors observed include the absence of yield generation (BTC.b does not offer staking rewards or yield) and the US regulatory shift, which creates a more permissive environment for commodity-adjacent crypto assets. Furthermore, we remain in close contact with the Lombard team, focusing on their regulatory compliance strategy and the regulatory exceptions they rely on in the jurisdictions mentioned.
4.2 Access Control Risk
4.2.1 Contract Modification Options
Here are the wallets controlling BTC.b on Ethereum:
- LombardTimeLock: Admin and owner of the BTC.b contract.
- Multisig1: Lombard-controlled 3/5 Safe, holds executor/proposer/canceller roles of the LombardTimeLock contract and can pause the BTC.b contract.
The following contracts power the BTC.b architecture on Ethereum:
- BTC.b: Upgradeable ERC20 contract for the BTC.b token controlled by LombardTimeLock.
- AssetRouter: Upgradeable contract, handles deposit/redemption orchestration and fee accounting.
- BridgeV2: Upgradeable contract, handles bridge execution for burn-and-mint transfers.
- LombardConsortium: Upgradeable contract, epoch-weighted multi-signature verifier.
A role-based access control mechanism is employed for BTC.b to manage sensitive functions:
| Controlling Addresses |
Role |
Functionality |
| LombardTimeLock |
DEFAULT_ADMIN_ROLE |
Can grant/revoke any role |
| BridgeV2, AssetRouter |
MINTER_ROLE |
Can mint BTC.b freely without any consortium proof or Bascule check |
| Multisig1, Multisig2 |
PAUSER_ROLE |
Can pause the contract |
| EOA1 |
OPERATOR_ROLE |
Manages configuration parameters and executes operational tasks |
| EOA1 |
CLAIMER_ROLE |
Watches BTC deposits, consortium proofs, and submits mint+fee transactions on the user’s behalf |
4.2.2 Timelock Duration and Function
A 1-day (86400 seconds) delay has been implemented for BTC.b contract upgrades via the LombardTimeLock.
4.2.3 Multisig Threshold / Signer identity
Lombard controlled Multisig1 (3/5 Safe) holds is the executor of the LombardTimeLock contract, which has the following role-based access control:
| Controlling Addresses |
Role |
Functionality |
| LombardTimeLock |
ROLE_ADMIN |
Can update roles, including the role admin role itself |
| Multisig1 |
EXECUTOR_ROLE |
Can execute all proposals, including role updates |
| EOA3, Multisig1 |
PROPOSER_ROLE |
Can schedule proposals, but can not schedule role updates |
| Multisig1, EOA3 |
CANCELLER_ROLE |
Can unschedule proposals, but can not unschedule role updates |
The 3/5 Safe Multisig1 has the following signers:
- 0xd7B78BF124eB327F23f75F5C49De0c3fa5d2265A
- 0x116744098070508c080B120A555B5453422b66eF
- 0x70B9b04b19D9015EfBe1db37BBe30Dd304737950
- 0xd775959eb15f6DfF24A267f988F6c2E2f769DeDa
- 0xDD48B7cfd0c2256E008B7C690Fbe47ca77CD6071
Note: This assessment follows the LLR-Aave Framework, a comprehensive methodology for asset onboarding and parameterization in Aave V3. This framework is continuously updated and available here.
Aave V3 Specific Parameters (BTC.b)
Final recommended parameters will be coordinated with @ChaosLabs
Price feed Recommendation
We recommend using the Chainlink BTC/USD feed to price BTC.b on Aave V3 Core.
Disclaimer
This review was independently prepared by LlamaRisk, a DeFi risk service provider funded in part by the Aave DAO. LlamaRisk is not directly affiliated with the protocol(s) reviewed in this assessment and did not receive any compensation from the protocol(s) or their affiliated entities for this work.
The information provided should not be construed as legal, financial, tax, or professional advice.
