The distinction between disclosing how to practice an invention and explaining how an invention works is important to understand when drafting patent applications.
The disclosure of an invention in a patent application must meet the “enablement” provision of the U.S. Code, which states that the “specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same.”
Preissuance submissions are a one-chance opportunity to present prior art in such a way that an examiner will be convinced to apply the prior art to reject pending claims in a patent application.
"The preissuance submission provision in the America Invents Act aims to bring the most relevant prior art to the examiner’s attention as early as possible during prosecution to enhance examination effectiveness and efficiency,” says Undersecretary of Commerce for Intellectual Property and Director of the U.S. Patent and Trademark Office (USPTO) David Kappos.
In August 2013, the U.S. Patent and Trademark Office (USPTO) reported a backlog of 591,665 patent applications waiting to be examined and an average total pendency (time from filing to end of examination) of 29.4 months.