(1)(2)Cl. X.—Books.Cl. X.—Books.0.Miscellaneous.1.Subject-matter—0.5Subject-matter—2.History.1. History.3.Science.2. Science.4.Art.3. Art.5.Fiction.4. Fiction—6.Language—4.5Language—7.English.5. English.8.German.6. German.9.French.7. French.10.Spanish.8. Spanish.11.Size—8.5Size—12.Folio.9. Folio.13.Quarto.10. Quarto.14.Octavo.11. Octavo.15.Duodecimo.12. Duodecimo.16.Binding—12.5Binding material—17.Leather.13. Leather.18.Rawhide.14. Rawhide.19.Cloth.15. Cloth.20.Paper.16. Paper20.Paper.
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Subject-matter, assumed to be the most important characteristic, is placed first. Any exhibit of mere material for binding, mere size, mere language, or mere subject-matter, would fall into the correspondingly entitled group. If, however, a book on history in German or a history in red leather, etc., were to be classified, it would be placed in subclass "History" in the subject-matter group, and a French book in green cloth would be placed in subclass "French" in the language group. That is, combinations of any characteristic with any one or more other characteristics may be placed in the group for that characteristic deemed the most significant and which is highest in the schedule. Again, by assigning a number to each generic title, each such title becomes thereby the miscellaneous group for varieties other than those indented under it, as well as for all varieties associating any characteristic with one or more of those standing lower down. Thus, a book of poems would belong in subclass "Subject-matter" and a 16mo volume bound with purple celluloid covers would belong in subclass "Size." So, by giving meaning to relative position, exhaustive arrangement is sought to be provided in a reasonable number of groups. To provide for other features that may be presented in future, an additional miscellaneous group may be added at the top (1), or the class title (2) might be deemed to represent the unclassified residue and a depository for future matter not specifically provided for.
(2) If the number of instances of association of subject-matter and binding materials, language and size, etc., are numerous, additional groups might be placed above the groups having the names of the characteristics, the fact of the existence of these groups indicating that the characteristic groups are for single characteristics only and do not include books having several different ones. In such case the schedule might be headed by a miscellaneous group, having either the title "Miscellaneous" or the title of the class, to receive associated characteristics not provided for by specific titles, immediately followed by subclasses for the particular associations found to be most numerous, as follows:
books.
Miscellaneous.Subject-matter and language.Subject-matter and binding material.Subject-matter.Language.Size.Binding material.
To illustrate further, selecting for the purpose a mass of objects presenting problems more nearly like those presented to the office inp. 14questions of patentability, let it be assumed that one is to classify the objects in a heap of metal scrap.
On looking over the material of the heap it is noticed that there are a large number of metal balls; some have holes through them, some are hollow, some are smooth on the outside, and some are hollow, smooth, and perforated, but they are all nevertheless balls, and accordingly all balls can be separated out and placed in a heap by themselves. Next, the presence of bars in the general mass is observed, some long, some short, some straight, some twisted, some of round stock, some of square stock, etc. These may be gathered together and placed in a separate pile at the left of the balls. It is further observed that there are many differently shaped annular bodies in the heap resembling generally the single links of a chain, some circular, some elliptical, some twisted, some made of round stock, some of square stock, etc. They are all nevertheless annular bodies; these may be placed in a separate pile at the left of the bars.
Now, in the remnant of the original heap, a sufficient number of similar single elements does not remain from which to make a smaller pile of elements. Different combinations of links, balls, and bars are, however, observed in the remaining heap. Some are combinations of links, some combinations of a ball and link, some of a bar and link, and some of a bar, link, and ball. These different combinations may be separated out in the order named and placed in separate piles. After all these things have been removed, there is left in the original heap a number of odds and ends or miscellaneous metal objects.
These several groups may now be arranged in the inverse order in which (in the particular illustration adopted) they have been removed, thus:
Miscellaneous (remnants of the original heap of scrap).Combined bar, link, and ball.Combined bar and link.Combined bar and ball.Combined link and ball.Chains.Links.Bars.Balls.
Knowing that objects of metal scrap not covered by the specific titles will be found in the miscellaneous group, and that the more complex specifically-named things are to be found first after the miscellaneous or at the left of the row of piles of materials thus separated and arranged, and the more simple things and parts farther to the right, the particular piles to resort to for the thingsp. 15wanted may be definitely determined. The same processes may be applied to each of the piles. Thus, balls, in the above illustration, may be divided into—
Balls—10. Hollow perforated.11. Hollow grooved.12. Hollow.13. Perforated.14. Grooved.
Again, the same processes may be applied to a mass of more diversified junk, of which the metal scrap may form one pile, rags another, old bricks another, old timber another, and, still another, timber having metal-straps, bolts, nails, etc., connected with it.
Superiority and inferiority.—In the arrangement of subclasses in a class, those groups that are related to each other as wholes and parts are arranged so that the wholes shall stand before the parts, and so that subclasses defined by effect or by special use shall stand before those defined by function or general use. For example, in the scrap illustration above, assuming the titles to be in a printed arrangement, "chains" precedes "links," which may be parts of chains, and if it had been desired to separate animal-drags, for instance, from the scrap, some animal-drags being particular adaptations of a bar, links, and ball, the group of animal-drags should precede "Bar, link, and ball." The words "superior" and "inferior" have been used to indicate this relationship. A class or subclass defined to receive a certain combination is superior to one defined to receive an element or a combination that is a part of that certain combination. A class or subclass defined to receive means for making a particular product, as an electric lamp, is superior to a class or subclass designed to perform a general function, as pumping air from a container. And whenever a question of assignment of a patent or application that contains matters of two or more groups bearing that relation is raised, the "superior" group is selected to receive it.
Further, in those instances in which groups are formed on different bases or different characteristics, not comparable with each other, and a patent is presented having matter falling in each group, that group which is highest in position is preferred in those instances where separate provision for means having both characteristics has not been made.
In cases of necessity, as where a combination is presented for which no class has been definitely provided, but classes exist into which the several parts would fall if separately claimed, the same practice that obtains in similar situations with respect to two or moresubclassesof a class may be followed with respect to two orp. 16moreclassesand the patent placed in that class which, in accordance with above-stated principles, should be deemed the "superior."
Definite positional relationship of subdivisions.—In the metal scrap example, above, division has been effected on the one basis of form or contour. If it had been desired to separate also on material, for example, if it were deemed important to locate all brass scrap, each of the groups based upon form could be divided into one ofbrassand onenot brass, or the entire heap could be divided intobrassandnot brass, and under the heading "brass" could be indented the various articles made of brass, and under "not brass" the various articles not made of brass, and this would double the number of divisions. If also it were desired to separate the lead articles in the same manner the number of classes would be tripled. But, as in the book illustration, it may be impracticable thus to multiply subdivisions, and the basis "form" having been selected as offirst-rankimportance, all divisions based upon form should be completed and kept together. Then, "material," having been selected as ofsecond-rankimportance, should be carried out with respect to all objects in which form is non-essential. If enough brass balls were found to render it advisable to make a subdivision of them, they should be assembled into a subclass indented under "balls" and not into a subclass indented under "brass." Having selected one basis asprimary, it should never subsequently be madesecondaryorvice versa. Some such restriction on modes of division appears salutary in a system of divisions designed to definitely limit search. The arrangement herein sought to be explained is susceptible of use to limit all searches for a single definitely stated invention to a subclass properly entitled to receive it or those indented under it, and to those subclasses above, which may include it as a part of an organization or specialized means.
As between coordinate groups divided on the same basis, there is no question of superiority and inferiority. The terms "superior" and "inferior" are useful in questions of relationship between combinations and subcombinations or elements thereof, and between groups founded on effect or product and those founded on simple function. The mere difference in complexity of mutually exclusive coordinate groups involves no relationship of superiority or inferiority. A subclass to receive a screw-cutting lathe is superior to a subclass to receive a lathe-headstock, a locomotive class is superior to a class to receive steam-engines, for the reason that the lathe is a whole of which the headstock is a part, and the locomotive is an organization of which the engine is an element. But the headstock subclass is not superior necessarily to the tailstock subclass simply because the headstock is commonly more complex than the tailstock. Yet arbitrary preference for classification in the headstock subclass may bep. 17established by position where an application or a patent contains claims for both.
Thus in a class that is founded on a well-chosen basis that brings together things bearing close resemblances to each other, all types that contain the elements essential to produce a complete practically operative means will be found in subclasses that have a position somewhere between the beginning and end of the list of subclasses of the class. Those that add features of elaboration of the essential types and those that are highly specialized to some particular purpose within the definition of the class will stand above the essential type subclasses, while those subclasses for parts and details will stand below those for the essential types.
Indented schedules.—In an indented schedule all subclasses in the first column reading from the left are species to the genus represented by the class title.[9]All subclasses indented under another subclass are species to the genus represented by the subclass under which they are indented. If a title has no number, it represents merely a subject-matter to be divided, a genus,—having no representatives except in the species under it. If a subclass having a generic title has a number, it not only represents a subject-matter to be divided into species but also all other species not falling within the titles indented. Although these relative positions might imply that only proximate species are indented one place, yet mechanical difficulties render it impracticable to so arrange that all species shall be indented under their proximate genera.
Indention properly carried out has a tendency to prevent in the process of logical division the logical fault of proceeding from a high or broad genus to a low or narrow species. This latter fault may inadvertently separate things that belong together. If, for example, it were desired to divide balls in the stated illustration according to material, an immediate division of balls into aluminum, zinc, glass,p. 18ivory, rubber, would be less useful than to divide into mineral materials and nonmineral materials as follows:
Balls—Mineral—Nonmetallic—Glass.Metallic—Aluminum.Zinc.Nonmineral—Vegetable—Rubber.Animal—Ivory.
However, it is evident that indention carried to its full extant, useful as it is in keeping analogous things together, would make the printing of schedules complex and unwieldy. Nevertheless, in the generalizing process necessary in logical division and arrangement, the divisions of species should always bementally indented, as it were, under theirproximategenera. Thus, under a genus unnamed may be arranged several species in juxtaposition, without actually printing the name of the genus, so that the schedule above may read:
Balls—Glass.AluminumZinc.Rubber.Ivory.
In an arrangement printed in idea-order, though relegating the genera mineral, nonmetallic, metallic, nonmineral, vegetable, animal, to the mind unaided by printed words, the different species of the same genus may be kept together except that species for which no title has been provided must go back to the subclass under which the named species are indented. Thus the arrangement above necessitates placing in subdivision "Balls" allcopperballs, whereas indention under proximate genus "metal" would have brought all metal balls together. In a finely divided classification, printing of titles for all genera is not practicable; hence great care ought to be directed toward grouping species according to the principles of arrangement herein outlined, noting that whenever a change of basis is made, a new genus is implied, and that subclasses for all other species of the same genus under whatever name, must be brought into juxtaposition as if indented under the implied genus.[10]
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Bifurcate division.—Most discussions of classification make reference to the so-called bifurcate scheme of division as the only one by which exhaustive division can be surely achieved. This is commonly illustrated by the ancient tree of Porphyry. By this method any subject it is desired to subdivide is first divided by writing the name of one selected species at one branch and writing at the other branch the name of the same species prefixed by "Not." Thus the Agassiz classification of living beings divides them first into sensible and not sensible (plants). A botanical classification divides plants into flowering and not flowering. A zoological classification divides animals into vertebrate and not vertebrate. By continuing the process of division in the same manner, the division is obviously exhaustive of the subject, there being always a negative subdivision to receive any subsequently created or discovered species. Although bifurcate division has been ridiculed by some, it is agreed by highest authority that it is the only plan of division by which one can be sure to have a consistent place for everything, or by which one can be certain that the divisions are mutually exclusive. It can be demonstrated that a classification schedule in which the relation of genera and species is shown by indentions, if correctly formed on the principles now sought to be applied in the revision of the Patent Office classification, is susceptible of conversion into a tree of Porphyry, while unlike the latter it is compact and wieldy.
Utility of arrangement according to resemblances.—The expedient of indicating kinds of relationship between several equally indented divisions by relative position has the following utility:
(1) A uniform rule is provided, applicable to all classes, for placing inventions that bear the relation of whole to part in subdivisions before those that bear the relation of a part to that whole, and those that are defined by a particular effect, product, material, or use before those that are defined by a function or an operation applicable generally to various effects, products, materials, or uses; whereby that portion of the schedule in which any invention belonging to any particular class should be found may be approached whether or not the investigator knows the name of the object sought for or the title of the appropriate subdivision.
(2) The substantial impossibility of dividing many branches of the useful arts exhaustively into a reasonable number of mutually exclusive or non-overlapping subclasses is compensated for; so that when the classifier or the searcher has an invention to place or to find including two or more different kinds of characteristics, for each of which a subdivision is provided, but no subdivision for the plural characteristics, it will be known that the invention should be in the subclass for that characteristic which stands before the subclass for the other characteristic.
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(3) It compensates for omission of some generic titles that if written in the indented schedule would lengthen specific titles to a cumbersome extent.
(4) It provides a rule for cross-referencing where several inventions are claimed bearing to each other any of the relationships indicated above, cross-referencing being necessary in one direction only where the matter illustrated is coextensive with the matter claimed.
(5) It definitely limits the field of search for anyunitary inventionin any class so arranged, as no patented invention having the limitations imposed by a unitary claim should be found in any subclass below the subclass properly defined to receive it or those indented under it. Parts of such inventions may be found below or following this subclass in the same class if these parts are within the class definition, or elsewhere in the useful arts if not within that definition. The unitary invention may be found in the subclass limited to it and certain subclasses arrangedaboveorbeforeit adapted to receive organizations of which it may be a part.
A complete system of arrangement should comprise (1) a display of the entire field of the useful arts in a manner to show the relation of the larger as well as of the smaller groups,—carrying the appropriate relationship as far as possible from the highest genera to the lowest species, the arrangement being such as would bring materials most nearly alike into closest propinquity regardless of the names they may be called by. (2) Supplementary to this classification arrangement by ideas there should be an alphabetical index of subclass titles, appropriately cross indexed, and additional titles of various technical and trade names of things classified under subclass titles.
Definition is indispensable in any classification and is very difficult. Every class must be defined and all of the groups under it. After definitions have been made and printed, they are sometimes found inadequate and must be supplemented by the definitions of other classes. This is unavoidable while the complete material remains unexplored. Definition in the strict logical sense is not to be expected, nor is it necessary. It is commonly sufficient if an explanation or comparison be made sufficient to direct the mind to the character of the contents of the group and indicate its limitations. Hitherto four of the five predicables of ancient logic have been mentioned, to wit, genus, species, property, and accident. In connection with definition, the fifth predicable, difference, is useful. To define a class, it is sufficient, generally, for the purposes of office classification, to state apeculiar property(not an accident) of the objects included in thep. 21class; and to define a species under the class it is sufficient to state the name of the class plus the difference—i. e., with the addition of the limitations that characterize the species.[11]This procedure in definition is susceptible of application from the highest genus to the lowest species. It is advisable to define the means included within a title without any introductory words, such as "this subclass includes inventions relating to," etc., treating the subclass for definition purposes as if it were a collection of concrete things, in the same manner as in a dictionary definition.
If patents were in all respects like material objects, cross-references and search-notes would not be necessary. Nails, screws, locks, hinges, and boxes are distinct things susceptible of definite separation and classification. Even though nails, screws, locks, and hinges form part of the box, the box is still a box, not a nail, screw, hinge, or lock. For the needs of the Patent Office classification, however, although a patent for a box must be classified with boxes, yet if a peculiar nail, screw, lock, or hinge is claimed in the same patent with the box, or even if any one of these customary accessories of boxes is illustrated, it may be necessary to provide copies of the patent for the box in each of the several classes provided for nails, screws, locks, or hinges.
Inasmuch as every relatively complex thing is made up of relatively simple things, it is obvious that all disclosures can not be cross-referenced. Any attempt to calculate the number of cross-references to be supplied if all disclosures of the subjects of invention were to be cross-referenced would show the number to be incalculable. It is necessary, therefore, to leave to the judgment of the classifier the propriety of cross-referencing unclaimed disclosures.
Should a patent contain a number of claims defining a number of differently classifiable inventions, complete cross-referencing fromp. 22the class in which the classification is made original into the other appropriate classes or subclasses should be effected,unlesscross-search notes or arrangement of subclasses with appropriate titles may be substituted to advantage.
Cross-referencing or cross-search notes are made, as a rule, from combination class to element class, but never or very rarely from the element class to the combination class in which it may be used. Thus cross-referencing should normally be downward in a schedule of subclasses. Search notes indicate parallel or otherwise related classes and subclasses, and those classes and subclasses in which analogous structures having different purposes but adapted to answer broad claims may be found.
By arbitrary rules of arrangement such as have been referred to in the section dealing with division and arrangement, a search may ordinarily be definitely limited to a certain number of subclasses, even where cross-references are not made. In such arrangement any given patent,if it be directed to one invention, may be searched in the subclass within which the definition places it or subclasses indented under it, and in certain subclasses above, whose titles will indicate that the invention might be included as a part of the matter defined to belong therein, but it would never have to be searched in any subclass following and not indented thereunder.
Each patent and each application discloses one or more means of the useful arts (using the term "means" to cover both processes and instruments in the sense in which it is used by Prof. Robinson), almost always more than one, since most new means are combinations of mechanical elements or acts. In some patents and applications the disclosure is coextensive with that which is claimed; in others there is matter disclosed but not claimed. The unclaimed disclosure may be as valuable as the claimed disclosure for purposes of anticipation, and the classification must provide for both. If the claimed disclosure belongs in one class and the unclaimed in others, the classifier must choose between two or more classes that one in which the patent or application shall be classified and those into which it shall be cross-referenced.
Claimed or unclaimed disclosure.—The claims of a patent are the statutory indices of that which the applicant believes to be new, they define an invention that has been searched by the Patent Office and no anticipation discovered for it. Future action must be based on inductions from past experience; none knows what the future lines of search will be; the only guides for future searches are the searches of the past; the evidence of past searches is the claimsp. 23of patents; they trace the course of invention. Furthermore, a presumption of novelty attaches to the claimed matter; no such presumption attaches to the unclaimed. The law requires every patent for improvement to show so much of the old as is necessary to explain the uses of the improvement. In practice much more than that is disclosed. Questions as to the proper placing of patents and cross-references would be diminished by the strict enforcement of Rule 36 of the Rules of Practice requiring that the description and the drawings, as well as the claims, be confined to the specific improvement and such parts as necessarily coöperate with it. In any event both the claimed disclosure and that which is unclaimed must be taken care of, one by cross-reference, and the disclosure selected for cross-reference is that to which no presumption of novelty attaches.
This practice of placing patents by the claimed disclosure is sometimes misunderstood. Its chief application is in determining classification in case of disclosures involving a plurality of main classes. Furthermore, the mere letter of the rule is not to be applied in preference to its spirit. Subcombinations claimed may be placed with the combinations, and in subordinate type subclasses patents must be placed sometimes by claimed and sometimes by not-claimed disclosures.
Diagnosis of pending applications.—What has been said relates to patents. The bearing of the practice of adopting the claimed disclosure as the basis of assignment of applications for examination has also to be considered.
Two pending applications claiming the same means very commonly differ in the kind and extent of disclosure. One application may disclose several inventions. Which of the several disclosures shall be selected as the mark by which to place the application? For instance, the typical wire-nail machine has a wire-feeding mechanism, a shearing mechanism, an upsetting (forging) mechanism, side-serrating mechanism, and pointing mechanism; it may also have a counting mechanism, a packaging mechanism, an electric motor on its frame for furnishing power; and, in addition, numerous power-transmitting and other machine parts, such as bearings, oil-cups, safety appliances, etc. The applicant may have made a complete new organization of nail-machine and may seek a patent for the total combination. He may have invented a new shearing mechanism and have chosen to show it thus elaborately in the place of use he had in mind, or he may have designed a new counter or a new oil-cup or a new power transmission, or even a new motor, and have given his invention this elaborate setting. The shears, the counter, the oil-cup, the power transmission, and the motor are separately classifiable in widely separated classes. How shall the application be diagnosed for determining its place in the office classification? When thep. 24specification and drawing disclose (as most of them do) several subjects matter of invention, though claiming only one, which of those several subjects matter shall control the classification?
The most natural procedure, at first thought, would be to classify on the totality of the showing, in which case the application for the nail-machine, supposed above, would be assigned to nail-making. But imagine the invention claimed by an applicant to be the counter. Then the examiner in charge of nail-making would have to search the class of registers with which he is not familiar. Suppose applicant No. 2 files an application for the same counter which he illustrates and describes in connection with a bottle-filling machine, and that, classifying on the totality of the showing, this goes to the division that has the class of packaging liquids. Now both the examiners in charge of bottle-filling and nail-making, knowing that counters are classified in registers, search the class of registers and also the pending applications in registers. After these examiners have made their searches, suppose applicant No. 3 files an application for the same counter, which he says may be used for counting small articles produced by automatic machines. Perhaps he shows the counter attached to a piece of conventional mechanism representing any manufacturing machine, mentioning, say, a cigarette or pill or cartridge-making machine. It has not occurred to either the the examiner of nail-making or the examiner of bottle-filling that the other might have any such application; nor does it occur to the examiner in charge of registers to search nail-making or bottle-filling. As the specification of the counter application mentions cigarette, pill, and cartridge-making machines to which the counter may be attached, the examiner in charge of registers may search those classes. Suppose that the counter proves to be new, and each of the three examiners allows a patent. Here now are three patents for the same thing. Of course, after allowance, the counter and all other disclosed inventions that give any suggestion of novelty are cross-referenced; but the primary purpose of a patent office classification (to aid in determining patentability) has failed in this instance.
In the imagined situation respecting pending applications, without doubt diagnosis and classification upon the invention claimed is necessary to effect the purpose of the office classification. Cross-referencing after issue can not undo that which has been done.
If no application save that of the nail-machine be pending, no duplication of patents occurs, but the labor of search is increased by reason of the unfamiliarity of the examiner with the inventions he has to search. After the patent is allowed he may find the entire combination of the nail-machine without the counter disclosed in a patent for a nail-making machine, so that as a nail-making machinep. 25this new patent is of no value as a reference. Very probably all of the other inventions illustrated (except the counter) are also old in their respective classes; but the examiner of nail-making can not tell this without extensive searches in those classes, so he notes cross-references for them all.
Difficulties due to varying ideas of claims.—Very troublesome questions are constantly arising as to whether an invention should be classified in a combination class or an element class. The point will be illustrated by example: A describes and illustrates an automobile having an internal-combustion motor and a friction-clutch in the motor transmission-gear. He states that the clutch is in the usual relationship to the motor and gearing, but claims a new clutch for whatever it may be adapted. B discloses an internal-combustion motor said to be for automobiles with transmission-gearing and a friction-clutch and claims "in an internal-combustion motor a friction-clutch," etc., specifying the form of the clutch. C makes the same disclosure, but claims "an internal-combustion motor having a specified clutch," while D, with the same disclosure, claims "the combination with the internal-combustion engine of an automobile" of a specified friction-clutch. E claims and illustrates only the friction-clutch. Should these be classified together? If so, in what class? Should a bearing composed of a specified alloy of copper, tin, and antimony, be classed as a bearing or as an alloy? Should a house painted with a mixture of linseed oil, lead oxid, and barium sulphate go to buildings or coating compositions? A lamp-filament of titanium and zirconium with electric lamps or with alloys? A building-block of cement, lime, sand, and carborundum, with building-blocks or plastic compositions? Whether these be diagnosed as combinations or as elements and compositions respectively, and classified accordingly, criticism will be aroused. The point in view is that although principles of patentability must be considered in a classification designed as an instrument to aid in determining patentability, convenience and accuracy of search and avoidance of voluminous cross-referencing may necessitate some arbitrary rule of classification to meet various and changing theories applied to the drafting and allowance of claims.
From the foregoing it will be evident that classification involves orderly logical processes of induction (supplemented by hypothesis), of definition and of deduction. After gathering a large number of facts generalizations are made from them and a hypothesis is found to be confirmed or modified by more extended research; the divisions are then defined; by correct diagnosis of other instances (as other patents) deductions may be drawn respecting the appropriate place for them in the classification.
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[1]An "art," in the sense of a single unitary invention, is a synonym of process, method, and operation. The term "art" is ambiguous in popular usage. In the phrase "useful arts" in the Constitution, it denotes the area of endeavor to which the patent laws apply. When the word "art" is used to specify some fragment of the useful arts, it commonly raises different notions in different minds. It may be correctly used to designateanydivision of the useful arts. It is as proper to speak of the art of grinding or the art of molding as of the art of metal-working or the art of brickmaking.
[1]An "art," in the sense of a single unitary invention, is a synonym of process, method, and operation. The term "art" is ambiguous in popular usage. In the phrase "useful arts" in the Constitution, it denotes the area of endeavor to which the patent laws apply. When the word "art" is used to specify some fragment of the useful arts, it commonly raises different notions in different minds. It may be correctly used to designateanydivision of the useful arts. It is as proper to speak of the art of grinding or the art of molding as of the art of metal-working or the art of brickmaking.
[2]A "use" is an application of a means to substance to produce an effect which may or may not be the necessary effect of the means in its normal operation. A catalytic may be used to ignite gas or to convert oleins into stearines. An ice pick may be used to hold a chalk line or prick holes in leather, etc.
[2]A "use" is an application of a means to substance to produce an effect which may or may not be the necessary effect of the means in its normal operation. A catalytic may be used to ignite gas or to convert oleins into stearines. An ice pick may be used to hold a chalk line or prick holes in leather, etc.
[3]By "natural law" in the useful arts is meant that uniformity of action which is manifested whenever any particular substance in any particular condition is brought into such relation with any particular manifestation of energy that the force exerted modifies or prevents modification of the form, nature, condition, or locus of the substance or modifies the manifestation of energy or both.
[3]By "natural law" in the useful arts is meant that uniformity of action which is manifested whenever any particular substance in any particular condition is brought into such relation with any particular manifestation of energy that the force exerted modifies or prevents modification of the form, nature, condition, or locus of the substance or modifies the manifestation of energy or both.
[4]A "property" may be described as any quality common and essential to the whole of a class but not necessary to mark out that class from other classes. Thus, all wheel tires may be said to possess annularity; but washers and finger rings are also annular. A "peculiar property" is one that not only always belongs to a class of objects but belongs to that class alone; thus a circle has the peculiar property of containing the greatest space within a line of given length, and catalytic substances have the power of setting up chemical reaction without themselves being changed.
[4]A "property" may be described as any quality common and essential to the whole of a class but not necessary to mark out that class from other classes. Thus, all wheel tires may be said to possess annularity; but washers and finger rings are also annular. A "peculiar property" is one that not only always belongs to a class of objects but belongs to that class alone; thus a circle has the peculiar property of containing the greatest space within a line of given length, and catalytic substances have the power of setting up chemical reaction without themselves being changed.
[5]An "accident" is any quality that may indifferently belong or not belong to a class without affecting the other qualities of the class. That a man's name is James is an accident telling nothing of the man's physique or character.
[5]An "accident" is any quality that may indifferently belong or not belong to a class without affecting the other qualities of the class. That a man's name is James is an accident telling nothing of the man's physique or character.
[6]"Effect" or "result" is the consequence of a process of the useful arts practiced with or without instruments. The effect of an instrument is the effect of its operation. Effects may be direct or indirect, proximate or remote, necessary or accidental."Product" is an effect consequent upon a process that changes the form, state, or ingredients of matter perceptibly and permanently, as distinguished from effects that are fleeting or involve no change in perceptible form, state, or ingredients of matter."Function" is the "action of means upon an object while producing the effect." (Robinson.) Functions may be direct or indirect, proximate or remote, necessary or accidental. The direct, proximate, or necessary function of the hammer in normal operation is impacting. Indirect, remote, or accidental functions of a hammer may be comminuting, forging, driving, etc.
[6]"Effect" or "result" is the consequence of a process of the useful arts practiced with or without instruments. The effect of an instrument is the effect of its operation. Effects may be direct or indirect, proximate or remote, necessary or accidental.
"Product" is an effect consequent upon a process that changes the form, state, or ingredients of matter perceptibly and permanently, as distinguished from effects that are fleeting or involve no change in perceptible form, state, or ingredients of matter.
"Function" is the "action of means upon an object while producing the effect." (Robinson.) Functions may be direct or indirect, proximate or remote, necessary or accidental. The direct, proximate, or necessary function of the hammer in normal operation is impacting. Indirect, remote, or accidental functions of a hammer may be comminuting, forging, driving, etc.
[7]Classification of the Sciences.
[7]Classification of the Sciences.
[8]Logical division is the process by which the species of which a genus is composed are distinguished and set apart. Physical division or partition is the process by which the parts of any object are distinguished and set apart. Metaphysical division is the process by which the qualities of a thing are segregated and set apart in thought.
[8]Logical division is the process by which the species of which a genus is composed are distinguished and set apart. Physical division or partition is the process by which the parts of any object are distinguished and set apart. Metaphysical division is the process by which the qualities of a thing are segregated and set apart in thought.
[9]Any class of objects may be called a "genus" if it be regarded as made up of two or more different kinds of objects or of two or more species. "Motors" is a genus when the class "Motors" is considered as divided into electric motors and nonelectric motors, or electric motors, spring motors, weight motors, current motors fluid pressure motors, etc. A genus is more extensive than any of its species but less intensive.A "species" is any class that is regarded as forming a part of the next larger class, "electric motors" being a species of "motors" and "motors" being a species of "energy transformers." A species is more intensive than the genus to which it belongs but less extensive.Every species may be a genus to another species until no further subdivisions can be made. This last indivisible species is termed theinfima species. Every genus may be a species to another genus until a point is reached where no further generalization may be made or thesummum genusis attained. In the Patent Office classification of the useful arts, thesummum genusis useful arts. Thesummum genusof the plastic arts would be plastics. Theinfima speciesin the useful arts evidently never can be attained."Proximate species" and "proximate genus" indicate, respectively, those species that are divided from a genus without intermediate genera, and those genera from which the species are directly divided. Motors, and not energy transformers, is the proximate genus to the species, fluid motors, electric motors, etc., while fluid motors, electric motors, etc., and not steam engines, alternating current motors, etc., are proximate species to motors.
[9]Any class of objects may be called a "genus" if it be regarded as made up of two or more different kinds of objects or of two or more species. "Motors" is a genus when the class "Motors" is considered as divided into electric motors and nonelectric motors, or electric motors, spring motors, weight motors, current motors fluid pressure motors, etc. A genus is more extensive than any of its species but less intensive.
A "species" is any class that is regarded as forming a part of the next larger class, "electric motors" being a species of "motors" and "motors" being a species of "energy transformers." A species is more intensive than the genus to which it belongs but less extensive.
Every species may be a genus to another species until no further subdivisions can be made. This last indivisible species is termed theinfima species. Every genus may be a species to another genus until a point is reached where no further generalization may be made or thesummum genusis attained. In the Patent Office classification of the useful arts, thesummum genusis useful arts. Thesummum genusof the plastic arts would be plastics. Theinfima speciesin the useful arts evidently never can be attained.
"Proximate species" and "proximate genus" indicate, respectively, those species that are divided from a genus without intermediate genera, and those genera from which the species are directly divided. Motors, and not energy transformers, is the proximate genus to the species, fluid motors, electric motors, etc., while fluid motors, electric motors, etc., and not steam engines, alternating current motors, etc., are proximate species to motors.
[10]In the Manual of Classification of the U. S. Patent Office the arrangement of subclasses has always been alphabetical, although in the Supplement containing definitions of revised classes the arrangement is numerical. If the latter schedule of "Balls" in the text had been printed in alphabetical order, it is apparent that the species "Aluminum" and "Zinc" of the genus Metal would be as widely separated as possible. In the former schedule of "Balls," in which the genus Metal is printed, "Aluminum" and "Zinc" come together. It is apparent that in an alphabetical arrangement allied species can not be kept together without printing every proximate genus. This fact, among others, indicates the advisability of abandoning the alphabetical arrangement in the classification manual and adopting the idea arrangement in the schedules of revised classes, supplemented by a consolidated alphabetical index of all subclasses.
[10]In the Manual of Classification of the U. S. Patent Office the arrangement of subclasses has always been alphabetical, although in the Supplement containing definitions of revised classes the arrangement is numerical. If the latter schedule of "Balls" in the text had been printed in alphabetical order, it is apparent that the species "Aluminum" and "Zinc" of the genus Metal would be as widely separated as possible. In the former schedule of "Balls," in which the genus Metal is printed, "Aluminum" and "Zinc" come together. It is apparent that in an alphabetical arrangement allied species can not be kept together without printing every proximate genus. This fact, among others, indicates the advisability of abandoning the alphabetical arrangement in the classification manual and adopting the idea arrangement in the schedules of revised classes, supplemented by a consolidated alphabetical index of all subclasses.
[11]A species contains all the qualities of the genus and more. These additional qualities form the "difference." The electric motor has the qualities that are common to motors and is differentiated by reason of the fact that electric energy is thereby converted to mechanical motion.
[11]A species contains all the qualities of the genus and more. These additional qualities form the "difference." The electric motor has the qualities that are common to motors and is differentiated by reason of the fact that electric energy is thereby converted to mechanical motion.
[12]Classification of a patent is said to be "original" in the class and subclass which receives the most intensive claimed disclosure, and in which the patent is indexed in the official classification indexes. "Original classification" is referred to as opposed to "classification by cross-reference."A "cross-reference" is a copy of a patent placed in a subclass other than that in which the classification is made original, in order to make available for search inventions disclosed therein and additional to that by which the patent has been diagnosed and classified.A "digest cross-reference" is a cross-reference formed from abstracts or extracts from a patent consisting of illustration and text cut from a photolithograph of a patent and mounted.A "search-card" is a sheet of the size of a photolithograph of a patent placed with the photolithographs of patents forming a subclass in the examining division and public search room, and containing suggestions for further search, and on the copy for the search room, a definition of the subclass."Search notes" are addenda to class and subclass definitions comparing other classes and subclasses with the one defined and giving directions for search when necessary to prosecute search beyond the defined class or subclass.
[12]Classification of a patent is said to be "original" in the class and subclass which receives the most intensive claimed disclosure, and in which the patent is indexed in the official classification indexes. "Original classification" is referred to as opposed to "classification by cross-reference."
A "cross-reference" is a copy of a patent placed in a subclass other than that in which the classification is made original, in order to make available for search inventions disclosed therein and additional to that by which the patent has been diagnosed and classified.
A "digest cross-reference" is a cross-reference formed from abstracts or extracts from a patent consisting of illustration and text cut from a photolithograph of a patent and mounted.
A "search-card" is a sheet of the size of a photolithograph of a patent placed with the photolithographs of patents forming a subclass in the examining division and public search room, and containing suggestions for further search, and on the copy for the search room, a definition of the subclass.
"Search notes" are addenda to class and subclass definitions comparing other classes and subclasses with the one defined and giving directions for search when necessary to prosecute search beyond the defined class or subclass.
(1) The basis of subdivision and assemblage of the means of the "useful arts" in the Patent Office classification is "art" within the meaning of "art" in section 4886, Revised Statutes. The direct, proximate or necessary art, operation or effect, rather than some accidental and remote use or application, should be selected. In all cases qualities or characteristics that persist through all accidental uses and that can be identified as permanent are to be preferred.
(2) The operative, instrumental, or manipulative arts, including machines, tools, and manufacturing processes, should be classified according to whether a single operation of one kind applicable to various materials to be used for various purposes is carried out by the claimed means, or whether plural operations are performed, which, combined, produce a special effect or special product.
Example: An instrument performing a plurality of operations peculiar to shoe-manufacture would be classified on the basis of shoemaking, because that instrument would be incapable of other use, while an instrument peculiarly adapted to drive nails would be classified on the basis of nailing, whether for nailing shoe-heels or other objects, and a hammer would be classified on the basis of its function as an impact tool even though described as for driving nails, and even into shoe-heels.
(3) Structures (passive instruments) will, in general, be classified on the basis of structure, either of special or general application, the essential functions and effects of static structures being resistive or the maintaining of forces in equilibrium.
Example: A structure recognized as peculiar to barriers of the kind known as fences would be classified in the special class of Fences, but posts, joints, beams, etc., recognized as having use in general building, even though described as used in fences, would be classified in a more general building class, such as Wooden Buildings or Metallic Building Structures.
(4) Compositions of matter and manufactured or formed stock or materials will be classified in accordance with the inherent character of the substance or material where possible, otherwise according to special use.
Example: A pure chemical is expected to be classified on the basis of its chemical structure and constituents, even though useful as a food, medicine, dyestuff, explosive, etc., and alloys on the basis of metallic composition, even though used for bearings, coins, tools, etc.; whereas a physical composition having no reason for existence except to function as a cleansing composition or a paint might have to be classified on the basis of its function as a detergent or a coating composition, respectively. Also a bimetallic layered foil, plate, or wire would be expected to be classified as metal stock even though designed for use for dental filler, plowshare, or electric conductor, and a woven textile fabric as a fabric even though described as used for a filter or apron for a paper-making machine.
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(5) The divisions or subclasses of a class should be made exhaustive, i. e., they should be susceptible of receiving any future invention that may fall within the scope of the class. The rule as usually phrased is: "The constituent species must be equal, when added together, to the genus." Exhaustive division may be secured by maintaining always a residual or miscellaneous subclass. The miscellaneous subclass represents the remainder of the original undivided material undefined except as the class is defined and may be accurately treated as if it had the class title.
(6) A second rule respecting the subdivision of a class is: "The constituent species must exclude each other." That is, the divisions or subclasses must not overlap. (See exception in Rule8.)
Example: If a number of balls of several different materials, several different conformations, or constructions, several different colors, were to be divided into glass balls, hollow balls, and red balls, this rule would be violated, because some balls would be glass, hollow, and red.
(7) A third rule respecting subdivision is: "The divisions must be founded on one principle or basis." The application of this rule will generally form divisions that do not overlap. (See exception in Rule8.)
Example: If a number of balls of several different constructions, several different materials, and several different colors were to be classified so as to provide a place for each kind of characteristic, they should be divided first, for example, according to construction into hollow balls and solid balls, each of these according to materials into glass balls, rubber balls, metal balls, wooden balls, etc., and each of the latter into red balls, blue balls, green balls, etc.
(8) When it is found that division into overlapping subclasses and on different characteristics is a lesser evil than an unwieldy number of subclasses that would otherwise result, then those subclasses based on characteristics deemed more important for purposes of search should precede in the list of subclasses those based upon characteristics deemed less important. (See Rule6.)
(9) In arrangement of subclasses or subdivisions the miscellaneous groups containing material not falling within any of the specifically entitled subclasses, should stand first; those subclasses defined by effect or special use should precede those defined by function or general use; those containing matter that is related to the matter of other subclasses as whole to part should precede those subclasses that contain the part; and those defined by a characteristic deemed more important or significant for search purposes should precede those defined by characteristics deemed less important.
Whenever superior rank has been assigned to any selected characteristicby placing divisions based upon it in advance of divisions basedp. 28upon other characteristics,this superiority should be maintained throughout.
Example: A partial schedule of Class 80 follows to illustrate the arrangement of subclasses:
Class 80.—Metal Rolling.
In this schedule the miscellaneous subclass is numbered 1, then follow three subclasses (2-4) of rolling plus another function, then four major subclasses (5-16) of rolling, merely, but applied to blanks of special form producing special products, then one special subclass (17) based upon a special class of material treated, then five subclasses (18-31) specialized in type and mode of operation, then general types of rolling mills (32-40), then various parts and accessories (41-59), then processes (60-66). This is the usual arrangement and is an exhaustive division for the art of metal rolling. Had there been miscellaneous subclasses for all combined operations of rolling plus some other function, a miscellaneous subclass for all mere rolling machines, either special or general, and a miscellaneous subclass for all parts and accessories, the requirements of exhaustive division would have been also satisfied.
In the illustrative schedule, there being no miscellaneous subclass for means having combined functions of rolling and another, any patent having claims for the combination of a means for rolling and a means for cooling would fall in subclass 1, Miscellaneous. In that subclass would also fall all "Mills," such as for rolling spiral conveyer-flights, the same not falling under any of the subclasses 32-40, no miscellaneous subclass of "Mills" and no special article-rolling subclass having been provided; also all parts or accessories, such as a water-cooled screen, peculiarly adapted to rolling-mills, there being no existing subclass of screens therein and no miscellaneous subclass of parts. The arrangement of subclasses in Class 80 requires that the combination of a furnace and a rolling-mill shall be placed in subclass 2, even if the combination be designed and adapted for rolling annular bodies (subclass 5) or tubes (subclass 11). Means special to rolling a tube between a concave and roll must be placed in subclassp. 2913 rather than in subclass 18. A work-reversing mill must be placed in subclass 33 rather than in subclass 34 even though it have three or more coacting rolls.
The rolling of "Screw-threads" having been given higher rank than a "Concave and roll" mechanism, any concave and roll mechanism limited for use in rolling screw-threads should be formed into a subclass indented under "Screw-threads" and not into a subclass "Screw-threads" indented under "Concave and roll."
(10) Class schedules are arranged with certain subclasses appropriately indented according to a commonly understood expedient. In a properly indented schedule subclasses in column at the extreme left are the main species (the proximate species) of the class. The titles and definitions of all subclasses proximate to the class (at extreme left) must be read with the title and definition of the class, as if indented under the class title one space to the right; so also with the titles and definitions of subclasses indented under other subclasses. If a title has no number (as in Class 80, "Mills"), it represents merely a subject-matter to be divided, assumed to have no representatives other than those in the species indented under it. If a title having indented species under it has a number, it not only represents a subject to be divided but also a subclass including all other species not falling within the indented titles. Indention does not indicate superiority or inferiority, but merely that the title and the definition of the indented subclass must be read with the title and definition of the subclass under which it is indented. A title selected in a scheme of subdivision to be of first importance and placed, therefore, in advance, should not thereafter be indented under a title selected to be of secondary importance and, therefore, having a lower position. (See Rule8.)
(11) A group of material may be divided on several different bases. "Use" or "purpose" or "object treated" may be adopted only when the "use" or "purpose" or "object treated" stamps upon the invention such peculiarities of operation or construction as to limit the applicability of the invention to the use or purpose named. (See Basis of Classification, Rule1.) A group based upon mode of operation also may be divided into subclasses (1) with a "functional" title, usually participial in form, and adapted therefore to receive machines, processes, and tools; (2) with special use, purpose, or object-treated title containing the name of the use, purpose, or object; (3) with "type" title, usually a name or a name with a qualifying adjective; (4) with a title of a part or subcombination, also a name.
Example: In Class 90, Gear-Cutting, Milling, and Planing, are to be found subclasses entitled "Gear-cutting," certain machines being peculiar to that use; also other subclasses with the general functional title "Planing," subordinate to which are the special use subclass "Planing, Soft metal," and the type subclass "Planers" divided into two coordinate subclasses, "Reciprocating bed" and "Reciprocating cutter," and several subordinate "part" subclasses, including "Tool-feeds" andp. 30"Tool-heads." The adjective form of the title "Planers, Reciprocating bed," indicates a type subclass. If the title had been Planers, Reciprocating beds, the indication would be that the subclass was a part subclass to receive planer beds only. In the class referred to for illustration, "Tool-feeds" and "Tool-heads" indicate subclasses for parts and not for types of planers having tool feeds.
(12) In arranging the divisions of a class, such arrangement should be sought as will minimize the need of cross-references. Search for any particular matter can not always be limited to one group without such extensive cross-referencing as would in some cases defeat the purpose of classification. Forming the subdivisions of a class according to the total similarities of the inventions, rather than according to some selected more or less important characteristic, and arranging them in the correct order of superiority and inferiority, with care to maintain throughout the schedule the relative positional values of the several selected bases of division, will ordinarily in a closely bonded class limit the search for any single invention to the subclass particularly suited to receive it and some subclasses preceding that one, excluding from the necessity of search the subclasses succeeding.
Example: In Class 80, Metal-Rolling, it would not be expected to find any tube-rolling mill lower in the schedule than the tube-rolling subclasses, but a tube-mill might be found higher up in "Heating and rolling," "Drawing and rolling," etc. No concave and roll combination should be found succeeding the subclass of "Concave and roll," but it may be found under subclasses above, such as "Tubes, Screw-threads," etc. No rolls should be found lower than the subclass of "Rolls," but they may be found in many subclasses above.
(13) Having some knowledge of the nature of the materials about to be classified, a tentative definition of a class to be formed may be framed, which may be either written down or merely carried in mind, to serve as a tentative guide. This tentative definition must be considered as subject to change to any extent by the fuller knowledge obtained by careful consideration of the material. After a full knowledge of the materials to be classified has been acquired, it will be necessary to frame a careful definition of the class, and also of each subclass whose title does not unequivocally indicate what is contained in it.
(14) A definition of any class should state the "qualities and circumstances possessed by all the objects that are intended to be included in the class and not possessed completely by any other objects." A proper definition should not ordinarily contain the name of the thing defined. "Definitions in a circle" are, of course, worthless. A definition should be exactly equivalent to the species defined and should not be expressed in obscure or ambiguous language, but should employ terms already defined or perfectly understood. It should not be in negative form where it can be affirmative. Ifp. 31the class of objects has a peculiar property, the naming of that may serve as a definition. If no peculiar property can be detected, the definition should name more than one quality or property. Several different classes may have one or more properties alike, but as the number is increased the likelihood of there being others having the same properties is decreased. The briefest possible statement of such properties or qualities as are possessed by all the objects of a class and not completely possessed by any other objects, which will suffice to distinguish the class from other classes and determine its position in the general classification, will be most satisfactory. To define any species, the genus having been defined, the genus should be named and the difference added. Of course, no generic definition should contain any limitation not characteristic of every species of the defined genus. In seeking qualities by which to describe a genus or species, no accident should be selected.
Example: Suppose there be marked out and defined as a genus all means whereby one form of energy is transformed into another form of energy and no more, and the genus be named energy-transformers. We may then name, as species, energy-transformers that are motors and energy-transformers that are not motors. Motors may be defined by merely naming the genus energy-transformers, and stating the difference, to wit, continuously transforming energy into cyclical mechanical motion. Then the definition will be: Energy-transformers that are adapted to continuously transform energy into cyclical mechanical motion. The non-motor division will retain the genus definition.
It would not be illuminating for a searcher having little familiarity with the textile arts to look under the title "Carding" and find that carding is defined as a means for carding fiber.
Even though the first steam-engine invented had been used to run a gristmill, the accident of its use as a part of a gristmill would hardly warrant the definition of a steam-engine as a means to grind corn. Nor would a hammer be properly defined as an instrument to drive nails or to crack nuts or to forge horseshoes, even though a patent should not mention any use other than one of these and should lay heavy emphasis on the special value of the hammer as a nut cracker, nail driver, etc.
(15) In those cases where the title is so obvious that definition is superfluous, explanatory notes may be substituted and will usually be found helpful.
(16) Inasmuch as nearly every patent discloses unclaimed matter that is classifiable separately from the claimed matter, it is clearly impossible to cross-reference every disclosure of every means in every patent. Many things must be taken as conventional, obvious, or well known, and the good judgment of the classifier is bound to be exercised in cross-referencing matter disclosed but not claimed to be the invention of the patentee.
(17) A mere part or element should rarely be cross-referenced from an element class to a superior combination class. An elementp. 32forming part of a combination in a superior class should, if claimed, be cross-referenced to the element class and also if not claimed if it seems to be not merely a conventional form, and patents having claims for more than one differently classifiable invention should always be cross-referenced unless such an arrangement of subclasses with search-notes is substituted as will guide the searcher to all places where the material may be found. Claimed matter additional to that which controls the classification, if belonging in the same class, should be cross-referenced into asucceedingsubclass. Cross-references of unclaimed disclosure may be in either direction.
(18) To supplement or take the place of cross-referencing, more or less elaborate search-notes are needed, giving directions and suggestions for further search, setting out the relationship between classes and subclasses, and drawing distinctions by example. Search-notes should indicate other classes or subclasses in which the subject-matter of the group to which the search-notes are appended is likely to form a part of a more intensive combination, also analogous matter that might serve as a reference for a broad claim. They need not, in general, indicate where parts or elements of the subject-matter which are common also to other classes can be found, because the index of classes contains the necessary information. For example, it is not necessary in every machine-class to indicate by search-notes where machine-elements and static parts may be found, nor in a class of wooden boxes to point out where the nails, screws, hinges, or locks that may form a part of the box are classified.
(19) Inasmuch as nearly every patent contains disclosure that is claimed and also disclosure that is not claimed, it has been deemed advisable to establish the general rule that where the claimed and unclaimed disclosures are classified in different classes or subclasses the invention both disclosed and claimed shall determine the placing of a patent (or a pending application) rather than any selected invention that may be disclosed but not claimed. "Not claimed" covers means that may form an element only of a claim as well as means not referred to in any claim. (See exceptions in Rules21to22inclusive.)
Example: A patent discloses and claims a dash-pot but illustrates it in such relation to a metal-planing machine as to utilize it for checking the movement of the bed at one end of its path, or in connection with an electric generator to aid in effecting the brush adjustment; the patent should be classified in the subclass of Dash-pots. If the classifier finds the disclosed organization of dash-pots and planer or dash-pot and generator more than a conventional illustration of an obvious use, he should note a cross-reference to Planers or Electricity, Generation. A patent discloses an internal-combustion engine associated with a specific form of carbureter; the claims relate to the engine parts only; the class of Internal-Combustion Engines should receive the patent, and a cross-reference should be placed in Carbureters. A patent discloses and specifically claims the combination of a rail-joint comprising abutting rails, fishp. 33plates, and specific bolts; the patent goes to an appropriate class of rail-joints, and if the bolt is more than a mere obvious conventional bolt, a cross-reference should be noted for the appropriate subclass of Bolts.
(20) The totality of the claimed invention should be selected when possible to determine the appropriate class in which to place a patent. The entire expression of the invention will usually be set forth in the most relatively intensive claim.[1]In a properly drawn patent there is at least one claim that will serve as a mark to indicate the classification of that patent.
(21) Where a patent discloses but does not claim a combination of proper scope to be classified in a combination subclass and claims merely a detail classified in a subclass lower in the schedule, both in the same class, if the subclasses are so related that the combination always involves the detail so that a search for the detail must necessarily be made in the combination subclass, the patent may be placed in the combination subclass. This avoids the need of a cross reference into the combination subclass, and a lack of a copy in the detail subclass is immaterial, as it is seen in the completion of the search through the combination subclass. (See Rule19.)
Example: A patent for a saw-making machine discloses dressing, jointing, and gaging mechanisms; it claims dressing and jointing only. There is a subclass for dressing, jointing, and gaging, and a subclass for dressing and jointing. In this case the patent may be placed in the first-mentioned subclass, as that must be searched always when the second-mentioned one is searched, cross referencing in this situation being of little value.