SIS - Service Indicators / Holds
Service Indicators are used in a variety of ways to designate certain services or data for a student. Most generally, service indicators (holds) are used to prevent enrollment (add, drop, or swap) and access to student records.
More Detailed information about Service Indicators is contained in a SIS training manual, located at https://learn.sis.wisc.edu/training/uploads/Service_Indicators.pdf