Creative works that are not protected by copyright are said to be in the “public domain”, a vast commons of material that everyone is free to enjoy, share, and build upon without restriction. While works can be dedicated to the public domain (by the creator forgoing their copyright), most are in the public domain because they are old enough for their copyrights to have expired. However, different countries and jurisdictions have varying laws about how and when copyright expires, meaning there exist, in effect, many public domains, despite the tendency to talk of “the public domain” as a singular entity.

How do I know if a work is in the Public Domain?

For works made prior to 1870 or thereabouts, it is generally safe to assume they are in the public domain the world over. But as we move toward the present, the status will start to vary according to the idiosyncrasies of copyright law in different jurisdictions, meaning a work might be in the public domain in one country but not in another. While copyright law can be frustratingly complex, most countries are covered by one of three main types of copyright term for historical literary and artistic works:

1. a term which lasts for 70 years after the creator’s death (relevant in UK, Canada, most of the EU, and South America);
2. a term which lasts for 50 years after the creator’s death (relevant to most of Africa and Asia);
3. a term which lasts for 95 years after the publication of a film or book, including any artworks featured within (relevant solely to the United States).

Within these basic frameworks there are, however, subtleties and exceptions. Determining if an artwork is out of copyright in the US can be particularly tricky, depending as it does on when (if at all) the artwork was first “published” (a term which itself is not clearly defined). To find out more about the ins and outs of US copyright law, we recommend this excellent chart from Cornell University and this tool from the Copyright Advisory Network. For the UK and the EU, you can try this handy set of flowcharts from Law Flow (from 2011, but this shouldn't affect the status of historical works). For info on all countries, see this useful set of pages on Wikimedia Commons.

Digital copies of public domain works

When we encounter a historical public domain work online it is in the form of a digital copy. While the underlying work itself is free from copyright, the digital copy can sometimes be subject to additional claims of copyright (or restrictions applied to its use). Rights and licences applying to historical works found online can therefore be broadly divided into two categories:

• The rights status of the underlying work, by which is meant the original work itself (the words of a book, the actual physical painting or drawing, a musical score, etc.).
• The rights status of the digital copy, by which is meant the digital reproduction of the original work (usually a scan or photograph).

Whether there should be such a distinction between the originals and their digital copies is hotly debated, and many doubt if it is legally valid to apply copyright to a basic reproduction of an out-of-copyright work. In 1999, in the US, a landmark case (Bridgeman v. Corel) ruled that exact photographic copies of public domain images could not be protected by copyright in the US because the copies lack originality.

Public domain works should stay in the public domain when they go online

It is our view that photographic reproductions of public domain works should not be subject to new copyright, and so public domain works should stay free from all restrictions on reuse when they go online. As encounters and interactions with works increasingly take place in the digital realm, mediated by such reproductions, this principle feels all the more vital.

Some might advance the argument that the institutions housing these works need to charge for reuse in order to raise vital funds. Putting aside the fact that providing open access to collections should be built into the very DNA of such institutions, a venture worth directing funds toward in its own right, image licensing departments rarely achieve noteworthy profit, and often make a loss. Those that do decide to open up their collections experience huge benefits, including fulfilling key missions to bring their content to the widest possible audience.

It is our mission at The Public Domain Review to champion this open way of sharing public domain works. It’s with this in mind that we have recently revamped how we present sources on our site, making the varying approaches to public domain works more transparent, including the implementation of an “open ranking” system for all the source institutions we feature. This is all part of the work we do to facilitate the use of, and encourage the growth of, an open digital cultural commons. It’s our belief that the public domain is an invaluable and indispensable good, which — like our natural environment and our physical heritage — deserves to be explicitly recognised, protected, and appreciated. If you would like to help us in our mission, then please do consider donating to the project.