🏛️AF2.0 Repurchasing Guide

Note: Anyone can become a repurchaser. No whitelisting is required.

Repurchasing Criteria

Once the money market sub-account is underwater, the account is publicly open to be repurchased.

To determine if the sub-account is underwater, the sub-account’s borrowing power (risk-adjusted collateral value) must be less than used borrowing power (risked-adjusted borrowed value).

Checking eligibility

To easily retrieve the data of the sub-account, you can call our view-only contract using the signature as follow:

• moneyMarketReader: 0x4913DEC75cC0e061Ba78ebbDb2584905760be4C6

• mmDiamond: 0x7389aaf2e32872cABD766D0CEB384220e8F2A590

• mmAccountManager: 0xD20B887654dB8dC476007bdca83d22Fa51e93407

The SubAccountSummary struct is as follow

Close factor

The close factor determines how much used borrowing power can be removed from the sub-account by repurchasing.

Example: Given

• close factor = 50%,

• USDC borrow factor = 0.9

• BUSD borrow factor = 0.8

• USDC debt = $500

• BUSD debt = $1000

1. Used borrowing power = (1000 / 0.9) + (500 / 0.8) = 1736.1111111111

2. The maximum used borrowing power that can be removed = 1736.1111111111 / 2 = 868.05555555555

3. BUSD can only be repurchased 868.05555555555 * 0.9 => 781.249999999995

4. USDC can only be repurchased 868.05555555555 * 0.8 => 694.44444444444

   • Since USDC debt is only $500, all of it can be repurchased

Executing Repurchase

In order to initiate the repurchase process, the repurchaser will need to call the following function @ 0x… (MMDiamond)

Repurchaser need to specify the debt token to be repaid in exchange of which collateral token.

By using the aforementioned example,

Given:

• close factor = 50%

• USDC borrow factor = 0.9

• BUSD borrow factor = 0.8

• USDC debt = $500

• BUSD debt = $1000

• ibBNB collateral factor = 0.8

• ibBNB priced at 300

• 4 ibBNB were posed as collaterals

• Repurchase reward rate = 5%

Repurchaser can repurchase 600 BUSD debt, which equivalent to 2 ibBNB by calling

Expecting to get 2 ibBNB * 105% = 2.10 ibBNB in return.

Converting ibToken to Token

In order to withdraw the ibToken from AF2.0, the repurchaser can call the following function @ 0x… (AccountManager)