Shared parameters like Sofistik_A in picture below, are used by Revit plug-in, some are system parameters and if you delete them, next time you open your Revit, plug-ins and Revit itself is going to generate them again.
If you want to know what those parameters are you check their names and param groups. Some might be from within the families and may not allow to delete.
Filter out with isVisible parameter and delete the once you want to delete