Yes. When a winner is selected and the uploaded design files approved, the legal ownership of the winning logo transfers to the Client from the Designer. All other logos, with the exception of the winning concept, remain copyrighted by the respective Designer.
Clients may make any modifications to the logo after the rights are transferred at their own risk.
Please note, any legal requirements to trademark your logo or perform other processes in order to legally register your new logo are your responsibility. Some clients hire lawyers to help them ensure a prospective new logo will be able to be registered.