Copyright does not last forever; when copyright expires, the work is considered in the public domain.
After copyright expires, and a work becomes part of the public domain, it can be freely copied, distributed, adapted, and performed without having to request permission from the author or having to pay any royalties.
While there is no legal requirement to attribute works that are in the public domain to their creators, citing public domain materials is an important part of maintaining academic integrity.
The public domain should not be confused with works that are available publicly (e.g. via the internet). Many publicly available works are protected by copyright.
Effective December 30, 2022, the general term for copyright protection in Canada is changing from the life of the creator plus 50 years to the life of the creator plus 70 years. This term extension was agreed to in the Canada - United States - Mexico Agreement trade treaty. The new term matches the general copyright term in the United States and several other countries around the world.
This change will not alter the status of any works that had previously entered the public domain under the 50 year term rule, but it will create two rules for determining whether works are protected by copyright or are in the public domain in Canada: