The feature was already there from Siebel Analytics 7.9 versions or probably from its earlier releases . We need to take some extra precautions before applying this in request filters which can be adopted as best practice in report development .
This ensures that the filter used in the request is not lost or overwritten by another filter or dashboard prompt that may supersede the request.
This option is only available if a value has been specified in the filter. If the filter item is set to “is prompted” then the Protect Filter option if not available.
To apply it on the filter in the Answers Request, select Filter Options button > Protect Filter. See below :