Circle has added Aave as a lending venue inside its Bitcoin-backed borrowing service for institutional Circle Mint clients, giving the product a second market after launching on Morpho alone in September.
The service, called Digital Asset-Backed Borrowing, launched on September 21, 2026. The mechanics run in three steps. A client deposits native Bitcoin with Circle, which mints a token called cirBTC on a 1:1 basis, backed by Bitcoin held in reserve at Circle National Trust. That token then serves as collateral in third-party on-chain lending markets, against which the client borrows USDC, Circle’s dollar stablecoin. The whole workflow runs inside Circle Mint, from deposit to repayment, and the client can add collateral or repay on its own schedule. Borrowed USDC lands directly in the client’s Circle Mint balance.
Circle is not the lender. Borrowing rates, collateral requirements, liquidation thresholds and available liquidity are set by the third-party protocols, and positions sit in smart wallets that customers control. Each venue follows its own liquidation procedures, so a borrower’s risk profile changes depending on where collateral is posted. Circle effectively acts as custodian and token issuer, while lending outcomes depend on code it does not control. That division of labor is the design’s defining feature, and also the part institutions have to internalize before sizing positions.
What Morpho’s numbers show
DABB debuted with Morpho on Arc, Circle’s EVM-compatible layer 1. Shortly after launch, market data showed nearly $18.86 million borrowed against a liquidity pool of $157.85 million, with the market’s liquidation loan-to-value threshold set at 86%. By October 2, Morpho deposits on Arc had surpassed $500 million, and the cirBTC/USDC market accounted for most of the chain’s early activity. That is real institutional uptake in under two weeks for a product that requires moving Bitcoin into a custody structure, and it explains why Circle moved quickly to add a second venue.
An 86% liquidation threshold leaves limited room in a sharp Bitcoin drawdown. Bitcoin has repeatedly fallen 30 percent or more within weeks in past cycles, and a position opened near the threshold faces forced liquidation well before an 86 percent loan-to-value line is breached at lower prices. Borrowers using Aave will need to learn that protocol’s parameters separately.
Aave’s own governance record on cirBTC adds useful context. The June proposal from AaveLabs noted that cirBTC had launched on Ethereum mainnet on June 8, 2026, and set conservative initial caps, 250 units supply cap and 20 units borrow cap, pending liquidity bootstrapping. LlamaRisk’s support was made contingent on that liquidity materializing, and the proposal flagged one specific risk: a compromise of Circle’s attester keys could authorize a mint on a destination chain that is not backed by a real burn. Morpho’s early volumes on Arc suggest demand exists; whether it is deep enough for Aave’s larger caps to fill is the open question the new integration will answer.
Who can actually use it
The service excludes customers based in New York, limiting the pool to institutions eligible under Circle Mint LLC. That exclusion matters because some of the largest US financial institutions are headquartered there and cannot use the product in its current form. Circle has not said whether a New York path exists.
The custody structure is worth restating because it is the part that differs from ordinary DeFi. cirBTC is issued by Circle International Bermuda Limited, the same affiliate structure behind USDC, with each token backed 1:1 by native Bitcoin held at a regulated Circle entity and segregated from corporate assets. Aave’s governance reviewed that structure in June and approved onboarding with a 73 percent loan-to-value and a 78 percent liquidation threshold in the v3 Core market, materially more conservative than Morpho’s 86 percent. That difference alone will route risk-averse borrowers to Aave and yield-maximizers to Morpho, and the split will itself become a live read on institutional risk appetite.
Adding Aave changes the competitive picture between lending protocols. Morpho had the cirBTC market to itself, and that exclusivity drove most of its early Arc activity. A second venue means borrowers and lenders can now split between two protocols, and the two markets will compete on rates and risk parameters for the same collateral. Liquidity may also fragment, which cuts borrowing costs when both venues are deep and raises them when neither is.
Circle said support for additional protocols may follow as the product develops, and that cirBTC could expand to more networks over time, in line with its multichain interoperability work. For institutional Bitcoin holders, the pitch is unchanged: keep BTC exposure, access USDC liquidity, and manage the path between them without selling. The new venue just means there are now two doors to walk through, with very different terms behind each.
Watch two numbers from here. The first is cirBTC supply on Aave versus Morpho, which will show where institutions actually prefer to post collateral once both venues are live. The second is the borrow rate spread between the two markets, which will reveal whether competition between protocols actually lowers costs for borrowers, as Circle’s framing implies, or whether thin liquidity keeps both expensive. USDC borrowing rates on Aave’s Ethereum core market have swung between roughly 4 and 14 percent over the past month depending on utilization, so venue choice can move annual costs by double digits on the same position.
There is also a broader signal in the timing. Circle launched Arc as its own chain this year and has been stacking institutional products on it, from tokenized funds to this collateral system. Aave’s arrival on Arc-adjacent workflows gives the chain a second blue-chip DeFi name alongside Morpho, and for Aave it means a new stream of regulated collateral flowing into markets that have otherwise depended on crypto-native deposits. Both sides have reasons to make the integration work, which is usually when these things actually ship.