• the invention of the electronic digital computer was put into the public domain in 1973 by the decision of one of the longest federal court cases in the history of the United States?
• before Nielsen BookScan began tracking point of sale data at bookstores, nobody knew how many copies were being sold of literary works that were published by multiple publishers and had entered the public domain?
• Russian photography pioneer Karl Bulla (pictured) left more than 200,000 glass negatives that are now in the public domain?
• AT&T once released designs for 83,539 equivalent transforms of a circuit into the public domain just to deny their competitors the ability to patent them?

Facts on topics related to Public domain

Copyright

• Scottish bookseller Alexander Donaldson sold cheap copies of books after their copyright had expired, in disregard to London booksellers' opinions on literary property?
• British music publisher Boosey & Hawkes owns copyrights to much major 20th century music, including works by Bartók, Bernstein, Britten, Elliott Carter, Rachmaninoff, Steve Reich and Stravinsky?
• Lawrence Turner, who presented a Parliamentary petition calling for W. S. Gilbert's copyright on the libretti of Gilbert and Sullivan operas to be extended indefinitely, was the grandson of comic actor George Grossmith who starred in them?
• the United States Air Force does not own the copyright to its official service song, "The U.S. Air Force"?
• the first copyright act, the Statute of Anne or "An Act for the Encouragement of Learning" (pictured), became law almost 300 years ago?
• under the United States' doctrine of substantial similarity, a work can be found to infringe copyright even if the wording of the text has been changed?

Mashup (music)

• it took only six weeks for Max Tannone to mash parts of 30 Radiohead and Jay-Z songs for the album Jaydiohead?
• there are over 90 mash-ups of the Kersal Massive's demo song?