How Does Inverse Finance FiRM Work?
Inverse Finance FiRM is a fixed-rate lending protocol that uses a novel DOLA Borrowing Rights (DBR) mechanism to let borrowers lock in interest rates. With $48M TVL and a redesigned architecture after two 2022 exploits on its predecessor, its B- grade reflects innovative design improvements (dual oracle, personal collateral escrows) offset by the untested nature of the DBR mechanism and the protocol's exploit history on earlier products.
TVL
$23M
Sector
Lending
Risk Grade
B-
Value Grade
D+
Core Mechanisms
6.2.4
NovelFixed-rate borrowing via DOLA Borrowing Rights (DBR) — borrowers purchase DBR tokens that decay over time to cover interest, locking in fixed rates
Novel: DBR is a unique DeFi primitive — a consumable token representing the right to borrow DOLA at a fixed rate. Unlike variable rates, the rate is fixed at DBR purchase time.
6.1.4
NovelPersonal Collateral Escrows — each user's collateral is held in an isolated smart contract, preventing co-mingling across users
Novel: per-user escrow contracts for collateral isolation, a design not used by other major lending protocols.
6.4.4
Dual oracle system — uses the lower of Chainlink spot price or 48-hour pessimistic price oracle (PPO) low for collateral valuation
Redesigned after 2022 exploits. Conservative oracle approach using minimum of two sources.
6.3.2
Standard fixed-spread liquidation with oracle-based triggers
Standard liquidation mechanics, triggered when collateral value falls below threshold
1.4.3
DOLA stablecoin — partially algorithmic stablecoin used as the borrowing currency on FiRM
DOLA maintains peg through various mechanisms including FiRM lending and AMO strategies
How the Pieces Interact
DBR tokens decay continuously while active. If DBR market becomes illiquid or prices spike, borrowers cannot replenish their DBR allowance, leading to forced position closures regardless of collateral health.
The pessimistic oracle (48h low) provides conservative pricing but may lag during rapid recoveries, keeping collateral valued lower than market for extended periods and triggering unnecessary liquidations after volatility events.
All FiRM borrowing is denominated in DOLA. A DOLA depeg above $1 makes repayment more expensive, while a depeg below $1 could incentivize excessive borrowing — both scenarios create instability.
Creating individual escrow contracts per user increases deployment costs and the total smart contract surface area. A vulnerability in the escrow template affects all users simultaneously.
What Could Go Wrong
- Historical oracle manipulation exploits — Inverse Finance suffered two oracle manipulation attacks in 2022 ($15.6M and $5.8M) on its now-retired Anchor product. While FiRM was redesigned with a dual-oracle system (Chainlink + 48h PPO low), the pattern of oracle-related vulnerabilities warrants continued scrutiny.
- DOLA Borrowing Rights (DBR) sustainability — DBR is a novel DeFi primitive that decays over time and must be replenished to maintain borrowing positions. If DBR market liquidity dries up or prices spike, borrowers could face forced position closures.
- Personal Collateral Escrow complexity — FiRM uses per-user escrow contracts to isolate collateral, preventing co-mingling. While this improves safety, the proliferation of individual contracts increases smart contract surface area.
- DOLA stablecoin peg dependency — all borrowing on FiRM is denominated in DOLA. A DOLA depeg event would disrupt borrowing costs and potentially trigger liquidations.
DBR Liquidity Crisis Forcing Mass Position Closures
ModerateTrigger: DBR token liquidity drops below $500K across all DEX pools while outstanding FiRM borrows exceed $30M, causing DBR price to spike 5x+ above normal levels
- 1.DBR market liquidity thins as sellers exit and demand remains constant from active borrowers — DBR price spikes, making fixed-rate borrowing effectively much more expensive than the rate locked in at position opening
- 2.Borrowers with expiring DBR allowances cannot affordably replenish, causing their positions to become liquidatable — Mass liquidations triggered not by collateral depreciation but by DBR market failure
- 3.Liquidation wave pushes collateral onto market, depressing prices for FiRM-accepted collateral types — Cascading liquidations as collateral price drops trigger more position closures
- 4.DOLA demand drops as borrowing becomes uneconomical — DOLA peg pressure as a key source of demand disappears
Risk Profile at a Glance
Overall: B- (35/100)
Lower score = safer