Circle announced cirBTC, its institutional wrapped Bitcoin, in May 2026. Lending protocols are the most obvious early demand center: roughly 40% of all wBTC supply sits in Aave, Morpho, and Sky markets as collateral against USDC and USDS borrows. This article walks through how cirBTC will likely slot into the five largest onchain lending venues once Circle ships, what collateral parameters governance forums are already debating, and which oracle feeds underwrite the risk.
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Note: cirBTC is "coming soon, subject to regulatory approvals" per circle.com/cirbtc. Listings and parameters below reference governance discussion threads and existing wrapped BTC precedent, not live markets.
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Wrapped BTC dominates DeFi collateral after stablecoins. wBTC alone collateralizes roughly $4B of borrows across Aave V3 and Morpho Blue. Lending protocols want cirBTC because Circle's compliance posture, attestation cadence, and regulated custody address the single biggest institutional objection to wBTC: opaque multi-sig custody and offshore counterparty risk.
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Aave V3, Morpho Blue, Sky, Spark, and Compound V3 are the five venues with active or pending governance signal around cirBTC. Aave's chain coverage and Morpho's permissionless market creation give cirBTC the fastest paths to deep liquidity. Sky and Spark would route cirBTC into USDS borrow markets, mirroring the existing wBTC vault.
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Aave V3 is the largest single venue for wrapped BTC collateral. The protocol runs separate liquidity pools per chain, so a cirBTC listing means a governance proposal per network. Based on the precedent set by wBTC and cbBTC listings, expect Aave to list cirBTC first on Ethereum mainnet, then extend to Arbitrum and Base within 60 to 90 days if oracle coverage and supply depth justify it.
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Aave Risk parameters for wrapped BTC assets historically cluster around 73% LLTV, a 76% liquidation threshold, and a 7% liquidation bonus. cirBTC will likely launch with conservative borrow caps (around 100 BTC equivalent) that step up as Circle publishes attestation history and onchain supply grows.
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Morpho Blue is the permissionless counterpart. Anyone can deploy a cirBTC/USDC or cirBTC/USDS market the moment Circle deploys the token contract, picking their own LLTV, oracle, and interest rate model. Expect MetaMorpho curators (Gauntlet, Steakhouse, Re7) to spin up cirBTC vaults within days of launch, not weeks.
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Morpho's permissionless design means cirBTC markets at 86% LLTV (the standard "aggressive" tier) are possible from day one, paired with Chainlink's BTC/USD feed. Lower-LLTV institutional markets at 70% with redundant oracle setups will run in parallel for treasury-grade borrowers.
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Sky (formerly MakerDAO) already accepts wBTC as collateral for USDS borrows through its core vaults. A cirBTC vault would mirror the wBTC parameters: 74% LLTV, a stability fee in the 5% to 7% range, and a debt ceiling capped initially around $50M to $100M while the Sky Risk Core observes utilization.
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Spark Protocol, the Sky-aligned lending market built on Aave V3 forks, would carry cirBTC as collateral against USDS borrows with similar parameters. Spark's tighter integration with the Sky Savings Rate makes it a natural home for institutions that want to mint USDS against cirBTC and park the proceeds in sUSDS yield.
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Compound V3 isolates each base asset (USDC, USDT, ETH, wETH) into its own Comet instance. cirBTC would list as collateral inside the USDC and USDT Comets on Ethereum and Base, paralleling the existing wBTC and cbBTC slots. Expect 75% collateral factor, 80% liquidation factor, and a borrow collateral factor near 70%.
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The table below summarizes likely launch parameters based on each protocol's wBTC precedent and current governance discussion. Treat values as directional, not final.

All five protocols will almost certainly use Chainlink's BTC/USD price feed as the primary oracle for cirBTC, since cirBTC is 1:1 backed and redeemable for native BTC. The depeg risk is the redemption gateway, not the underlying spot price. Some markets will layer a secondary feed (Chronicle on Sky, Pyth on Morpho's faster markets) and a circuit breaker that pauses borrowing if cirBTC trades more than 0.5% off BTC for a sustained window.
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Expect liquidation bonuses in the 5% to 8% band, identical to wBTC. The novel risk for cirBTC is the redemption path: liquidators need confidence that they can offload cirBTC at peg, either through Circle Mint redemption or onchain DEX depth. Initial borrow caps will stay tight until cirBTC pools on Curve, Uniswap V4, and Maverick build at least $50M of two-sided depth.
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For suppliers, the differentiator is custody transparency. wBTC's BitGo plus BiT Global custody model is sound but opaque relative to Circle's monthly attestation cadence on USDC. cirBTC inherits that attestation discipline, which lets institutional suppliers underwrite counterparty risk more cleanly. For borrowers, the difference is mostly cosmetic until supply depth matches: wBTC's $9B head start means tighter borrow rates for the next 12 to 18 months.
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cirBTC's launch on Ethereum and Arc gives lending markets a clean native-BTC collateral with Circle's compliance backing. Routing cirBTC between chains for collateral rebalancing is exactly the workflow that Eco Routes orchestrates: borrowers can deposit cirBTC on Aave Ethereum, mint USDC, route it to Base, and redeploy in a Morpho cirBTC/USDC market without manually bridging each leg.
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Parameters reference governance forum threads and existing wBTC precedent as of May 2026. Final cirBTC listings will be set by each protocol's risk service provider (Gauntlet, Chaos Labs, Block Analitica) after Circle confirms launch terms.