A Derived Contract is a contract that shares allotment and rates with the Master Contract, with a rate delta (difference) expressed as a percentage or a fixed amount.
Specifically, the derived contract shares by default with the Master Contract:

A derived contract is defined by:
It is possible to not inherit certain elements from the Master Contract by deselecting the relevant option. In this case, the section you want to customize for the derived contract will be available in the command menu. In addition to this, you can set a booking and/or check-in window that is valid only for the derived contract, as well as change the room type.
A derived contract can also be blocked independently from the Master Contract using the dedicated toggle switch.
Please note the following behaviors:
Note: Any Promotions will be applied to the delta defined in the derived contract
if there are no Tariffs in the Master Contract, the availability defined in the Derived Contract will not be shown
the Min Stay values set in a Derived Contract must be more restrictive than those defined in the Master Contract; otherwise, the Min Stay rules from the Master Contract will apply