No you do not own the domain name. The owners of the domain name is the RIPN who delegates the domain name to the Registrant (the entity who has made application to register the domain name).
As long as the Registrant maintains the domain name upon suitable nameservers and does not use the domain name for illegal purposes, they can exercise the use of the domain name in their possession.
Annual checks take place, by the RIPN, who makes sure that the domain resides on the registered nameservers. If it is found that the domain does not reside where it is suppose to be, it can be cancelled without notification. This check is notified to the administrator of the domain name, Domain Name Services. If there is any problems Domain Name Services will contact the Registrant of the domain name.
It is suggested that you keep an up to date record of your registrant details with Domain Name Services.