Gets or sets the scope limits for property value inheritance, resource key lookup, and RelativeSource FindAncestor lookup.
Assembly: PresentationFramework (in PresentationFramework.dll)
Certain boundaries in the element tree set to deliberately limit the scope of inheritance behavior, to a force resource lookup to check the application resources, or to prevent a RelativeSource FindAncestor lookup from querying the current element or any further. RelativeSource FindAncestor lookup occurs when a binding uses a RelativeSource that has its Mode property set to the RelativeSourceMode::FindAncestor value.
If you want your derived class to set this property, you should do so within the static constructor or in other initialization routines.