When a .SE domain name is deregistered it enters quarantine (a post-expiry grace period) and is blocked from re-registration for 40 days. Only after that period can the domain be registered again by anyone.
The rule in short
- Quarantine period: 40 days from deregistration.
- Release time: the date shown next to date_to_delete in the IIS domain search tool, but not before 04:00 UTC (06:00 Swedish summer time, 05:00 Swedish winter time).
Why the domain still shows as registered
During quarantine we still display the domain as registered to the previous owner, because they retain the option to renew the domain name during this period.
Checking the release date
The Internet Foundation (IIS) provides an official .SE domain search tool. You can access it on the IIS website and look for the date_to_delete field to see exactly when the domain becomes available for registration.