After a patent application is filed with the U.S. Patent and Trademark Office (USPTO), it gets assigned to an art unit and a patent examiner in that art unit who is responsible for reviewing the application, doing a prior art search, and determining whether to grant a patent.
Examiners at the USPTO have expertise in specific technology areas, and to ensure a high-quality examination of a patent, it is important to match the technology of the patent to the expertise of an examiner.
The details of the assignment process are not important here, but the idea is that a patent application is “classified,” which means that codes are assigned to indicate the technological subject matter of the patent, and then an art unit and examiner are selected with expertise in that technology.
In the past, this process was manual. People would review patent applications to assign classification codes, and then other people would determine the art unit and examiner to be assigned using the classification codes.
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