Your funds aren't held in custody by Bitso while they're in Boxes. They sit in a smart contract of the Morpho protocol, in a vault curated by Gauntlet, a company specialized in protocol risk management.

Because Boxes is a lending product with variable yield, it doesn't carry the same guarantee as a traditional banking product. There's no deposit insurance like a bank account has, and that's part of why the rate can vary over time.

You can check the vault's full details, including liquidity, total deposits, the curator, and collateral exposure, at any time. See the Boxes vault on Morpho.