[NIP-82] List a Balancer osETH/ETH leveraged vault (Arbitrum)

Summary

We propose listing an ETH Balancer leveraged vault on Notional V3 Arbitrum. The vault would allow users to borrow ETH from Notional’s Arbitrum deployment at a fixed or variable rate and LP the proceeds in the Balancer ETH/osETH pool to earn pool rewards.

Proposal & parameters

We propose listing an ETH leveraged vault using the Balancer ETH/osETH pool as a strategy. We propose listing that leveraged vault strategy with the following parameters:

Vault Parameters Proposed Value
LiquidationRate 1.03 (3%)
MinCollateralRatioBPS 0.13
MaxDevelerageCollateralRatioBPS 0.23
MaxRequiredAccountCollateralRatioBPS 1.00
Maximum vault capacity 500 ETH
Minimum borrow size 2 ETH
feeRate5BPS 20 (100 BPS)
ReserveFeeShare 80%
Strategy Parameters Proposed Value
maxPoolShare 25%
oraclePriceDeviationLimitPercent 1.50%

By adding this leveraged vault strategy to Notional, the protocol will effectively accept Balancer ETH/osETH pool tokens as collateral. We propose setting the maximum vault capacity up to 500 ETH to cap the maximum amount of ETH that can be borrowed from Notional to enter that specific strategy. In practice Notional governors will increase the maximum capacity of the vault in line with demand and ETH liquidity up to the 500 ETH maximum vault capacity threshold. We propose setting the maximum pool share at 25% such that users won’t be able to enter the vault if the protocol already holds more than 25% of Balancer ETH/osETH pool tokens.

We propose setting the maximum leverage at 8.7X such that if a user deposits 1 ETH, he can at a maximum borrow 7.7 ETH from Notional to LP in the Balancer osETH/ETH pool. This maximum leverage ratio (minimum collateral ratio) aims to protect the protocol against a large decrease in the pool’s token value. Setting the strategy’s maximum leverage ratio at 8.7X ensures the protocol would be protected against a decrease of -8.85% in the pool’s token value (ETH/osETH LP tokens) relative to the vault’s borrow currency (ETH). It’s important to note that the vault’s maximum leverage ratio is set as a precautionary buffer to protect the protocol against a decrease in the value of pool tokens relative to users’ debts.

We propose setting the MaxDeleverageCollateralRatio at 0.23, this implies that a liquidator can lower an account’s leverage ratio to 5.3X if it ever breaches the max leverage ratio of 8.7X. This ratio is set such that an account that gets liquidated will subsequently be able to withstand another large decrease in the strategy token price before becoming eligible for liquidation again thereby lowering the risk of an account being liquidated multiple times in a short period of time.

We propose setting the minimum borrow size at 2 ETH and the vault liquidation discount at 3%. These parameters aim to maximize the likelihood of successful liquidations under stressed market conditions (ex: high gas environment). To do so, a liquidator’s revenue from the liquidation discount must be sufficient to cover liquidation expenses (gas cost, slippage, Dex fee, price basis). By setting the minimum borrow size at 2 ETH and the liquidation discount at 3%, liquidators will likely receive at a minimum 0.06 ETH. Based on historical market conditions such a liquidation discount is likely cover a liquidator’s expenses under most scenarios.

We propose setting the leveraged vault fee at 1.0% such that borrowers will pay a 1.0% premium on their borrow rate when entering the vault. We propose setting the reserve fee share at 80% such that 80% of the borrow premiums will go to Notional reserves and 20% are paid to nETH holders.

We propose setting the oraclePriceDeviationLimitPercent to 1.50%. The oraclePriceDeviationLimitPercent prevents users from entering or exiting the vault if the implied pool prices deviate from the oracle prices by more than 1.5%. This parameter mitigates oracle attack vectors while being flexible enough to ensure user can enter and exit the vault even if oracle prices slightly deviate from on-chain prices in between updates.

Risks

Oracle

We propose using the Chronicle osETH/ETH oracle to check that the implied Balancer osETH/ETH pool price is in line with the overall market.

Liquidity

osETH’s primary liquidity venue on Arbitrum is this Balancer pool. This presents some illiquidity risk, but that risk is greatly mitigated by osETH liquidity on Ethereum which is several times larger than the liquidity on Arbitrum.

osETH was deployed to Arbitrum using Wormhole, so fast bridging to Ethereum is available for the asset. This means that if the price of osETH declines on Arbitrum, users could arbitrage Arbitrum prices vs. Ethereum osETH liquidity. This greatly reduces the osETH illiquidity/liquidation risk for Notional on Arbitrum.

Resources