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US Patent Written Description Requirement


The specification is a written description of the invention and of the manner and process of making and using the invention that concludes with the claims to the invention, which must begin on a new page. The specification must include a written description of the invention and of the manner and process of making and using it, and is required to be in such full, clear, concise, and exact terms as to enable any person skilled in the technological area to which the invention pertains, or with which it is most nearly connected, to make and use the same.

The specification must set forth the precise invention for which a patent is solicited, in such manner as to distinguish it from other inventions and from what is old. It must describe completely a specific embodiment of the process, machine, manufacture, composition of matter, or improvement invented, and must explain the mode of operation or principle whenever applicable. The best mode contemplated by the inventor for carrying out the invention must be set forth.
In the case of an improvement, the specification must particularly point out the part or parts of the process, machine, manufacture, or composition of matter to which the improvement relates, and the description should be confined to the specific improvement and to such parts as necessarily cooperate with it or as may be necessary to a complete understanding or description of it.

For inventions involving computer programming, computer program listings may be submitted as part of the specification as set forth in 37 CFR 1.96(b) and (c). Other than for a reissue application or reexamination proceeding, the pages of the specification (but not the transmittal letter sheets or other forms), including claims and abstract, must be numbered consecutively, starting with 1, the numbers being centrally located above or preferably below, the text. The lines of the specification must be 1.5 or double spaced (lines of text not comprising the specification need not be 1.5 or double spaced). It is desirable to include an indentation at the beginning of each new paragraph, and for paragraphs to be numbered (i.e., [0001], [0002], [0003], etc.).

It is preferable to use all of the section headings described below to represent the parts of the specification. Section headings should use upper case text without underlining or bold type. If the section contains no text, the phrase “Not Applicable” should follow the section heading.

The specification should have the following sections, in order:

(1) Title of the Invention.
(2) Cross Reference to related applications (if any). (Related applications may be listed on an application data sheet, either instead of or together with being listed in the specification.)
(3) Statement of federally sponsored research/development (if any).
(4) The names of the parties to a joint research agreement if the claimed invention was made as a
result of activities within the scope of a joint research agreement.
(5) Reference to a Sequence Listing, a table, or a computer program listing appendix submitted on a compact disc and an incorporation by reference of the material on the compact disc. The total number of compact disc including duplicates and the files on each compact disc shall be specified.
(6) Background of the Invention.
(7) Brief Summary of the Invention.
(8) Brief description of the several views of the drawing (if any).
(9) Detailed Description of the Invention.
(10) A claim or claims.
(11) Abstract of the disclosure.
(12) Sequence listing (if any).

Title of Invention

The title of the invention (or an introductory portion stating the name, citizenship, residence of each applicant, and the title of the invention) should appear as the heading on the first page of the specification. Although a title may have up to 500 characters, the title must be as short and specific as possible.

Cross-Reference to Related Applications

Any nonprovisional utility patent application claiming the benefit of one or more prior filed copending nonprovisional applications (or international applications designating the United States of America) under 35 USC §§120, 121 or 365(c), or to a provisional patent application under 35 USC §119(e) must contain in the first sentence(s) of the specification following the title, a reference to each prior application, identifying it by the application number or international application number and international filing date, and indicating the relationship of the applications, or include the reference to the earlier application in an application data sheet under 37 CFR §1.76. See 37 CFR 1.78. Cross-references to other related patent applications may be made when appropriate.

Statement Regarding Federally Sponsored Research or Development (if applicable)

This section should contain a statement as to rights to inventions made under federally sponsored research and development (if any). See MPEP §310 for more information.

Reference to Sequence Listing, a Table, or a Computer Program Listing Compact Disc Appendix (if applicable)

Any material submitted separately on a compact disc must be referenced in the specification. The only materials accepted on compact disc are computer program listings, gene sequence listings, and tables of information. All such information submitted on compact disc must be in compliance with 37 CFR §1.52(e), and the specification must contain a reference to the compact disc and its contents. The contents of compact disc files must be in standard ASCII character and file formats. The total number of compact discs including duplicates and the files on each compact disc must be specified in the specification.

If a computer program listing is submitted and is over 300 lines long (each line of up to 72 characters), the computer program listing must be submitted on a compact disc in compliance with 37 CFR §1.96, and the specification must contain a reference to the computer program listing appendix. A computer program listing of 300 or less lines may be, but is not required to be, submitted on compact disc. The computer program listing on compact disc will not be printed with any patent or patent application publication.

If a gene sequence listing is to be submitted, the sequence may be provided on a compact disc in compliance with 37 CFR §1.821-1.825, in lieu of submission on paper, and the specification must contain a reference to the gene sequence listing on compact disc.

If a table of data is submitted, and the table would occupy more than 50 pages if submitted on paper, the table can be submitted on a compact disc in compliance with 37 CFR §1.58, and the specification must contain a reference to the table on compact disc. The data in the table must properly align visually with the associated rows and columns.

Background of the Invention

This section should include a statement of the field of endeavor to which the invention pertains. This section may also include a paraphrasing of the applicable U.S. patent classification definitions or the subject matter of the claimed invention.

Also, it should contain a description of information known to you, including references to specific documents, which are related to your invention. It should contain, if applicable, references to specific problems involved in the prior art (or state of technology) which your invention is drawn toward. See MPEP 608.01(c) for more information.

Brief Summary of the Invention

This section should present the substance or general idea of the claimed invention in summarized form. The summary can include the advantages of the invention and how it solves previously existing problems. Preferably, problems are identified in the Background of the Invention section. A statement of the object of the invention may also be included. See MPEP 608.01(d) for more information.

Brief Description of the Several Views of the Drawing

Where there are drawings, you must include a listing of all figures by number (e.g., Figure 1A) and with corresponding statements explaining what each figure depicts.

Detailed Description of the Invention

In this section, the invention must be explained along with the process of making and using the invention in full, clear, concise, and exact terms. This section should distinguish the invention from other inventions and from what is old and describe completely the process, machine, manufacture, composition of matter, or improvement invented. In the case of an improvement, the description should be confined to the specific improvement and to the parts that necessarily cooperate with it or which are necessary to completely understand the invention.

It is required that the description be sufficient so that any person of ordinary skill in the pertinent art, science, or area could make and use the invention without extensive experimentation. The best mode contemplated by the inventor of carrying out the invention must be set forth in the description. Each element in the drawings should be mentioned in the description. See MPEP 608.01(g) for more information.

Claim or Claims

The claim or claims must particularly point out and distinctly claim the subject matter which the inventor or inventors regard as the invention. The claims define the scope of the protection of the patent. Whether a patent will be granted is determined, in large measure, by the scope of the claims.

A nonprovisional application for a utility patent must contain at least one claim. The claim or claims section must begin on a separate physical sheet or electronic page. If there are several claims, they must be numbered consecutively in Arabic numerals.

One or more claims may be presented in dependent form, referring back to and further limiting another claim or claims in the same application. All dependent claims should be grouped together with the claim or claims to which they refer to the extent practicable. Any dependent claim that refers to more than one other claim (“a multiple dependent claim”) shall refer to such other claims in the alternative only. Each claim should be a single sentence, and where a claim sets forth a number of elements or steps, each element or step of the claim should be separated by a line indentation.

Abstract of the Disclosure

The purpose of the abstract is to enable the USPTO and the public to determine quickly the nature of the technical disclosures of your invention. The abstract points out what is new in the art to which your invention pertains. It should be in narrative form and generally limited to a single paragraph, and it must begin on a separate page. An abstract should not be longer than 150 words. See MPEP 608.01(b) for more information.


The applicant for a patent will be required by law to furnish a drawing of the invention whenever the nature of the case requires a drawing to understand the invention. However, the Director may require a drawing where the nature of the subject matter admits of it; this drawing must be filed with the application. This includes practically all inventions except compositions of matter or processes, but a drawing may also be useful in the case of many processes.

The drawing must show every feature of the invention specified in the claims, and is required by the Office rules to be in a particular form. The Office specifies the size of the sheet on which the drawing is made, the type of paper, the margins, and other details relating to the making of the drawing. The reason for specifying the standards in detail is that the drawings are printed and published in a uniform style when the patent issues, and the drawings must also be such that they can be readily understood by persons using the patent descriptions.