Brown & Michaels
How do I read a patent - the Specification
The "specification" of a patent is all of the written part of the patent, except for the first-page information and the claims. After each section on this page, we will give a reference to the Code of Federal Regulations (CFR) or Manual of Patent Examining Procedure (MPEP) which discusses the section.
The specification has the following parts:
(A) Title of the Invention: (See 37 CFR 1.72(a).) This is pretty obvious - the title will be at the beginning of the specification. Many years ago, patents had very short, very generic titles - "Tool", "Device". Today, titles are longer and more specific, especially in patent based on applications from some other countries. Japan, in particular, tends toward very long titles.
(B) Cross-Reference to Related Applications: (See 37 CFR 1.78 and MPEP Section 200.) If this patent is related to other patents, or based on earlier-filed US applications, it will be stated right after the title. This would include patents based on provisional applications, or which are divisions, continuations or continuations-in-part of other applications. If the earlier applications became patents before this patent issued, the patent numbers will usually be noted here. Sometimes foreign priority applications are listed here, but it is not required. This information may duplicate information on the first page.
(C) Statement Regarding Federally Sponsored Research or Development: (See MPEP Section 310). If the invention was developed under a contract from a US Government agency, the Government retains some rights in the patent. The contract will define these rights, but at a minimum they will have a paid-up license to practice the invention.
(D) Reference to a "Microfiche Appendix": (See 37 CFR 1.96(c) and MPEP Section 608.05). Sometimes a very lengthy listing of a DNA sequence or computer program is required as part of the patent disclosure. This may be supplied on microfiche or, more commonly today, on a CD-ROM. If such an appendix was provided, there will be a note under this heading. Copies of these appendices are available from the USPTO, for a price.
(E) Background of the Invention: The specification should set forth the Background of the Invention in two parts:
(1) Field of the Invention: This is a very broad description of the area of technology into which the patent falls. Traditionally, the field of the invention is stated in two sentences. The first is sort of a paraphrasing of the class definition, the second is similar to a subclass definition. For example, "The invention pertains to hand tools. More specifically, the invention pertains to adjustable wrenches."
(2) Description of the Related Art: This section discusses the "prior art" - that is, what was known before the invention. This will often include references to specific patents or other documents, and might include a discussion of shortcomings of prior patents.
In years past, the background or summary sections of patents often had long listings of the problems the invention was to solve, often stated in terms of "objects of the invention" ("A problem of prior art wrenches is that they slip off bolts. It is an object of the invention to provide a wrench which does not slip off bolts."). This is much less common today, in large part because patent examiners in other countries (the EPO, particularly) object to lists of "objects", and because these lists had been used to limit or invalidate patents, where a defendant could prove the invention did not, in fact, meet its "object".
(F) Brief Summary of the Invention: A brief summary or general statement of the invention as set forth in 37 CFR 1.73. The summary is supposed to be directed toward the invention, rather than the disclosure as a whole. The summary may point out the advantages of the invention or how it solves problems previously existent in the art (and preferably indicated in the Background of the Invention). In chemical cases the summary should point out in general terms the utility of the invention. If possible, the nature and gist of the invention or the inventive concept should be set forth. In practice, this section is often a paraphrase of the Abstract (or vice-versa).
The Summary most often reflects the broadest claim, as it stood when the application was filed. Because in US practice the specification is rarely amended when the claims are narrowed, the summary of the invention is often broader than the claims which finally issue after examination.
(G) Brief Description of the Drawing: A reference to and brief description of each Figure in the drawing(s) as set forth in 37 CFR 1.74. This really means brief. One sentence, only, in the form: "Fig. 1 shows a side view of the frammis of the invention", or "Fig. 6 shows a sectional view of the frammis, along the lines 6-6 in fig. 5."
Definition of terms you'll see in this section (see also our page on drawings):
- "perspective" - the view is simulated 3-D
- "sectional" - the figure is of a cut through the invention, like slicing an apple through the core. If the section is taken from another drawing, the other drawing should have a "section line" indicating where the cut is made, and which direction it is "looking".
- "cut-away" - similar to a section, but only part of the invention is revealed - like cutting away part of the apple peel to show the seeds in one spot.
- "detail" - a part of another figure, enlarged. The other figure should have the area of detail called out, usually by dotted or dashed lines.
- "exploded" - the parts of the invention are shown physically separated, with lines indicating where they go.
- "plan view" - same as top view
- elevation view" - same as front view.
(H) Detailed Description of the Invention: A description of the preferred embodiment(s) of the invention as required in 37 CFR 1.71. The description should be as short and specific as is necessary to adequately and accurately describe the invention.
This section of the specification is used to describe the various embodiments of the invention in great detail. Each of the figures will be explained, and, at least in theory, every reference number in the drawing will be called out and named in the detailed description. The detailed description will often include a method of making an invention, or a method of using it. Sometimes there will be one or more "examples", especially in method patents or in inventions which have chemical or biotech elements, where it is necessary to demonstrate the utility of the invention.
"Embodiments" are versions or variations on the invention. The various embodiments are supposed to all be the same invention - the rule is "one invention to a patent, and one patent to an invention". If the Examiner felt that two embodiments were, in fact, two independently patentable inventions, they might have been split out into two applications and might now be two patents (the second one is called a "divisional" of the first).
Because US practice seldom amends the specification to correspond to the claims, you will usually find that the detailed description in the parent patent and any divisional are identical, with only the claims differing between the two. That is, if the original application described two different inventions, the Examiner would have required the applicant to pick one to proceed with, and any claims directed to the other invention would be withdrawn. The applicant could file a divisional application with only the claims which were withdrawn from the first application, and the result would be two identical patent specifications, describing both inventions, with the claims to the first invention in the parent patent, and the claims to the second invention in the divisional patent.
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