Public domain pictures are images that are copyright free. There are no limits on the distribution or modification of public domain images. These images may be used personally or commercially without payment or even attribution to the original artist or photographer.
While the usage of public domain pictures is largely without restriction, determining the true copyright status of a work can be more difficult. Many public domain pictures were once copyrighted but have entered the public domain as their copyrights have expired. Images that have entered the public domain this way can be particularly difficult to identify, and avoiding copyright infringement often requires additional research.
For images copyrighted prior to 1978 but after 1 January 1923, protection of an image expires 95 years from the date of the original copyright. Images copyrighted after 1 January 1978 are protected for 70 years beyond the date of the date of death of the copyright holder. In general, photographs and artwork copyrighted in the U.S. before 1922 have entered the public domain.
Sometimes, artists can voluntarily choose to have their work enter the public domain. In this case, a statement from the creator of the work will generally accompany the image. Only statements that contain the phrase “This work has been entered into public domain” are fully guaranteed to be liability free. Images labeled “royalty free” and “creative commons” may have different usage restrictions than public domain pictures.
Voluntary submission and expiration of copyright are the two most common ways that images enter the public domain, but there are various other case-specific ways that a graphic may become public domain. For example, most photographs and drawings used in publications by the United States government are also public domain pictures. Images from anonymous authors or images that have never been copyrighted can also make their way into public domain usage.
The complexity of copyright laws can make using images obtained from the Internet risky. A third-party promise of copyright status is generally not a valid legal defense in most copyright infringement cases. Ultimately, the person using the photograph will be held legally responsible.
Once a public domain graphic has been modified, it becomes a derivative work and is eligible for copyright protection. For example, if an artist would incorporate public domain pictures into a collage, then that collage would be eligible for copyright protection. Copying the picture from the collage could be considered copyright infringement even though the source of the unmodified picture was public domain.
It is also important to note that, while photographs may be public domain pictures, the specific content of the photograph may not be. For example, if a trademarked product is included in a picture, that trademark is still protected and may not be used commercially without the permission of the entity that owns the trademark. Individuals in photographs may also have cause for civil litigation if they did not give their permission to be photographed.
Serious efforts have been made to create uniform international copyright laws, but laws can still vary among regions. Generally, the use of images must conform to the laws of the specific region in which they will be used. For international use, public domain pictures must be public domain in every region in which they appear.