The Classification of Patents

by United States. Patent Office

(23) Where, as in the case of patents that show and claim a combination that as matter of common knowledge is not new except in one of its elements, to classify a patent strictly in accordance with rule would result in placing the patent where it would serve no useful purpose as a reference and having to cross-reference it to a class where it would serve a useful purpose, it is best to classify the patent in the class to which the element would take it. (See Rule [19].)

Example: A patent claiming a wheeled vehicle, broadly, in combination with an internal-combustion engine comprising a cylinder, a crank-case, a piston and suitably-connected crank, a valve opening into the crank-case, and a valve in the piston opening into the cylinder, may be advantageously classified as an internal-combustion engine notwithstanding the alleged invention is for a motor vehicle.

(24) In order to meet the situation respecting the classification of those patents that indiscriminately claim an article of manufacture defined only by the material of which it is made and those patents that claim those materials, leaving to the specification information regarding the designed uses, patents for articles defined only by their ingredients specifically set forth may be placed in the composition of matter or material class. (See Rule [19].)

Example: A patent having a claim for a cutter made of an alloy of iron, tungsten, and manganese would be classified with Alloys; a patent claiming a box made of paper composed of two layers united by a solution of asphaltum should go to the class of Laminated Fabric and Analogous Manufactures, rather than to paper boxes; and a patent for a house having its exterior coated with equal quantities by volume of carbonate of lead and oxid of barium suspended in a vehicle of linseed-oil would be classified as a paint rather than as a house.

(25) An alleged process of utilizing a specifically-defined composition or material which consists in merely applying it to the use it was designed for may be classified as a composition or material rather than as a process. (See Rule [19].)

Example: A process of painting the bottom of a marine vessel which consists in applying thereto a composition consisting of sulphate of copper, powdered metallic zinc, chlorid of antimony, and hyposulphite of soda, in a vehicle of linseed oil, would be more usefully classified as an antifouling paint than as a ship, as the invention would hardly be distinguishable from a paint claimed as such and described for use on submarine surfaces.

(26) An alleged process consisting merely in the use of a particularly-defined machine or similar instrument operating according to its law of action will ordinarily be classified in the class or subclass[p. 35] where the machine belongs. But if in addition to defining the operation of a particular machine the claim also specifies acts not performed by the machine, the classification should be in the class or subclass in which the process belongs. (See Rule [19].)

Example: Thus a claim for a method of rolling an iron plate which consists in passing an iron blank between a pair of rolls arranged horizontally in juxtaposition one above the other and geared together so as to rotate in opposite directions, and causing an idle roll supported in bearings on the roll-housings to bear against the central portion of the surface of one of the first pair of rolls on the upper side thereof, should be classified as a rolling-mill, while if to that claim were added the steps of doubling the sheet after one passage between the rolls, again passing between the rolls, again doubling, and then passing the now four-ply pack between the rolls sidewise or turned 90 per cent to the direction in which it had previously been fed, the classification should be with processes of sheet-metal manufacture.

(27) In the absence of settled rules defining permissible joinder of inventions, there may be in one patent claims for one or more or all of the classes of invention named in the statute, to wit, machine, art, manufacture, and composition of matter. There may also be claims to several more or less related inventions in the same statutory class of invention but each belonging to a different industrial art. (1) Where different main classes are involved, the patent will be classified by the most intensive invention, without regard to the statutory class to which it belongs. (2) Where different subclasses of the same class are involved, the patent will be classified in that one of the several subclasses defined to receive the several inventions which stands highest in the schedule of subclasses.

(28) Where a patent contains claims for all or a plurality less than all of the statutory classes, the general rule of preference or superiority of the several classes of subclasses is that represented by the following order, to wit: (1) Machine (or other operative instrument); (2) Art; (3) Manufacture; (4) Composition of matter. This order is, in a general way, the order of intensiveness of the several kinds of invention. (See Rules [29]-[35].)