Public Domain Day
Public Domain Day is an observance of when copyrights expire and works enter into the public domain. This legal transition of copyright works into the public domain usually happens every year on 1 January based on the individual copyright laws of each country.
The observance of a "Public Domain Day" was initially informal; the earliest known mention was in 2004 by Wallace McLean (a Canadian public domain activist), with support for the idea echoed by Lawrence Lessig. Several websites list the authors whose works are entering the public domain each January 1. There are activities in countries around the world by various organizations all under the banner Public Domain Day. 
January 1, each year. 2019: Tuesday
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