There are some minor differences in the way full and partial refunds and chargebacks are managed:
Full refunds are processed according to the original split. For instance, if $50.00 was deposited into an account and a refund occurs, this $50.00 will be deducted from that same account.
Partial refunds are taken from the marketplace's account, as we don't know which part should be taken from which account. However, if a split is defined in a /refund call, the refund will be processed according to the split.
Chargebacks can be configured to be fully taken from the marketplace's account. Another configuration for chargebacks is for the chargebacks to be taken from the sub-merchants accounts, according to the original split.