While issued patents and published patent applications make up a substantial majority of all prior art references, the USPTO can still issue a number of rejections based on non-patent literature (NPL). Non-Patent Literature is any document and/or publication that is not an issued patent or published patent application.
Some examples of non-patent literature include:
- Technical manuals;
- Conference presentations;
- Posters;
- Journal articles;
- Facebook posts;
- Blog articles; or
- Book
It is important to remember that prior art is anything that has been published and publicly accessible in any language anywhere in the world.