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No Rights Reserved - Public domain
When a work is not protected by copyright (either by design or the expiration of a copyright term) it enters the public domain, a realm where no rights are reserved.
Some Rights Reserved - Creative Common licenses
Open licenses, such as those provided by Creative Commons, allow copyright holders to grant permissions to users in a simple, straightforward manner, while still retaining specified rights - some rights reserved.
All Rights Reserved - Copyright by default
In copyright law, by default, all rights are reserved, or held, for the copyright holder.