When setting up a field dependency, admins set the behavior for the dependent fields using one of these behaviors: Read Only, Visible, Required, or Hidden. What kinds of document fields can be dependent fields?
The Dependent field cannot be a Standard Vault field. The following fields can be dependent fields:
- Standard object reference fields
- Custom fields
However, there are some exceptions where standard fields can also be dependent fields, such as Allow PDF Download, Document Title, Material Type, Event Type, etc.
Vault Help Documentation: Field Dependencies - Restrictions