Why are there “reserve capacity” in some courses?

For some UG courses, seats would be reserved for students in particular programs during the enrollment period. Students who have officially declared their major or minor (where applicable) in the specified programs can occupy the reserve capacity during this period. Most reserve capacity would be released as free seats when add/drop period starts.

Reserve capacity in PG courses would not be released as free seats unless the instructor / course department intends to do so.