What kind of patent literature belongs to primary literature?

Patent literature is the general name of official documents and publications produced by countries and international patent organizations that implement the patent system in the process of patent examination and approval. Early patent documents, called patent certificates or invention patent certificates, are exclusive legal documents granted to inventors. The patent specification, that is, the description of the invention, including the description of the exclusive right claim, was only a part of the legal document at that time.

Modern patent documents can be divided into three types according to their different functions: first-class patent documents, second-class patent documents and patent classification materials.

Patent documents, that is, all kinds of patent specifications that describe in detail the specific content of invention and creation and the scope of patent protection.

Secondary patent documents are various official publications that publish abstracts or patent names and patent indexes, such as patent bulletins and annual indexes.

Patent classification data is a reference book for managing and retrieving patent specifications according to the technical theme of the invention, including: patent classification table, classification definition, classification table index, etc.