The description in a patent application must enable other people to make and use the invention. It is not permitted to keep some aspects of the invention secret while attempting to patent it; full disclosure is required. A good description identifies the problem addressed by the invention, acknowledges what elements of the invention are already known, and clearly describes the new elements. New matter cannot be added to an application after it has been filed.

The PTO has recently become much more strict about drawing quality. Drawings must be consistent with one another, and must meet requirements for line weight, lettering size, page size and the like. The drawings must be consistent with the description, and every element recited in a claim must be illustrated, except for inventions which cannot be illustrated.

The claims are the legal definition of the invention. Claim drafting is an art requiring obedience to arcane principles including single-sentence construction, antecedent basis, explicit recitation, claim differentiation. A good claim identifies what is new about the invention that distinguishes it from the prior art. Claims may be amended subsequently, but cannot go beyond what is shown in the original drawings and described in the original description.

The Abstract is a short summary of the invention, without much legal consequence. Its purpose is to give searchers and examiners a quick understanding of the patent, once it is published.

An Application Data Sheet is a special form prescribed by the PTO in which inventor data and other pertinent information is reported. It is normally prepared by the person or firm who files the application.

The I.D.S. is an important part of most applications. It reports documents and information known to the applicant or his attorneys which may be pertinent to the question of patentability. Failure to reveal such information to the examiner may result in an inability to enforce the patent against infringers.

A declaration signed by each inventor is required in every case, with the exception of cases where an inventor is unavailable or refuses to sign, in which case the other inventors, or the owner of rights to the invention may sign of that inventor's behalf.

Recording an assignment is optional. If no assignment is filed, the patent will be granted to the named inventor(s). If an assignment is made before the issue fee is paid, normally the assignee will be identified on the face of the patent. Post-grant assignments can also be made.