REST fetching fields - required value is always false

Hi,

I am retrieving fields  via REST, url:

http://xxxx:8080/qcbin/rest/domains/DEFAULT/projects/xxxx/customization/entities/defect/fields

the returned xml contains all available fields, where <Required>false</Required> for all of them.

But when open ALM UI only number of fields are required (red colored with *)

What am I doing wrong?