This is one of a series of blog posts related to the NYPL Public Domain Release: discover the collections and find inspiration for using them in your own research, teaching, and creative practice.

Last month, The New York Public Library released over 180,000 high resolution images for download that we believe are “public domain,” by which we mean free of known U.S. copyright restrictions. The phrase “public domain” refers to things for which copyright has expired or does not apply. When an item is in the public domain, no permission from a copyright holder is necessary for someone to use or reuse that item. In recent weeks, we have received a number of requests for more information on the work that went into the release. I am proud to share with our users the work of the Copyright and Information Policy team (also known as the Rights team) did for this release and continues to do to expand access to our collections.

This release is a continuation of NYPL’s mission to advance knowledge. This commitment to providing free and open access to our collection is a core value at NYPL. In 2013, we published and implemented our policy on open bibliographic metadata, making a significant number of records available without restriction. In 2014, we released more than 20,000 cartographic works as high resolution downloads. By growing the number of high resolution images available for download, we are able to continue to serve a vital role in the intellectual fabric of American life.

A vibrant and robust public domain of books, art, film, music and other works is critical to libraries and our users. Artists and authors of all kinds rely on the public domain to create new expression, scholarship and knowledge. For example, many of today’s animated movies borrow heavily from the fairy tales and stories that are in the public domain. Building on the work of others helps fulfill the constitutional purpose of copyright law, which is to “promote the progress of science and the useful arts.”

For NYPL’s release of high resolution images, the Rights team at the Library invested significant time and effort to review these items. A primary role of this unit is to make the Library’s myriad collections more broadly available to researchers and to the general public by researching and analyzing rights issues. When we digitize an item from our collection, we review the potential copyright, trademark and other rights involved in our use of that item to avoid infringing the important rights of rightsholders. We use tools like reverse image searches and the Catalog of Copyright Entries in our research. We create and record information about the rights issues in collection items and store that information along with other data about the item in our repository. In particular, we attempt to make determinations regarding the copyright status of collection items under the laws of the United States.

Unfortunately, investigating the copyright status of collection items is not always easy. We often are not able to make conclusive or definitive determinations. This is due, in part, to the complexity of U.S. copyright law and changes to the law over the last one hundred years. For example, the publication date of an item can be a critical fact to determine whether the item is in the public domain. But the definition of publication is not always intuitive. For example, the broadcast of a speech on national television was not considered a publication of that speech.

Beyond the complexity of U.S. copyright law, another factor that makes it difficult to make conclusive copyright determinations is that we may lack key pieces of information about the item. For example, photographic prints often lack information about when they were taken or the name of the photographer. Without that information, we will have difficulty determining whether the copyright in that photograph was renewed, if renewal was necessary. While many tools have surfaced to facilitate determinations, the tools are only as good as the information that goes into them. We encourage anyone who may have more information about our items to contact us at digitalcollections@nypl.org.

When we are able to reach reasonable conclusions about what we believe the copyright status of an item is, we want to share that information with our users. We want to share that information in a way that is as clear and precise as we can be. That is why we have decided to use the phrase “no known U.S. copyright restrictions” instead of “public domain.” By using “no known U.S. copyright restrictions,” we want to express to our users that we were unable to find any indication that the item is still protected by U.S. copyright law. We also want to be sure our users understand that we are not a court of law, nor are we able to guarantee that we have not made a mistake in either the facts or the law.*

We will make more items available in high resolution as we continue our copyright status investigation. My team will be reviewing items that have already been digitized but lack a recorded copyright status determination, as well reviewing new digitization. That means each time you explore our digital collections, you will find new items available as high resolution downloads. Check out newly released public domain content at digitalcollections.nypl.org and the creative work it has facilitated at publicdomain.nypl.org.

*These items may be subject to rights of privacy, rights of publicity and other restrictions. It is your responsibility to make sure that you respect these rights.