What does a domain transfer mean?
The owner of a domain can transfer it at any time to another registrar via a service provider (MrDomain), due to reasons of cost, service, etc.
Most of the registration companies register the domains thru another ICANN accredited registrar, so it's possible that the processes can be slowed or impeded because of this situation.
With MrDomain you have the guarantee to work directly with an ICANN accredited registrar. There are only 13 accredited registrars in Spain.