Why is whois data not available for some sites?

Question

I am trying to check the whois details for a site uq.oz.au and not able to find any data. I have tried multiple whois engines. Could someone let me know why this is the case? Shouldn't registration information for the domain be public domain?

Note I have also checked http://whois.ausregistry.com.au but this also states that there is no data. However, if I navigate to www.uq.oz.au I do get the University of Queensland website. Can someone explain why this is the case or if I am not searching for it correctly?

Answer 1

According to Wikipedia, oz.au. is a legacy domain that resulted from a namespace move. Data may simply not have been ported to newer systems.