Guide to construction

Product-by-process claims

2.71 A product-by-process claim is one in which the product is defined in whole or in part in terms of the process used to manufacture the product, instead of solely by structure, composition, properties or characteristics (see Section L in Chapter 3 about its novelty assessment). For all practical purposes, product-by-process claims fall into either the statutory category of article of manufacture or composition of matter claims.

2.72 A claim to a product obtained by a process:

“Product X obtained/prepared by process Y”

is normally construed as a claim to the product per se, irrespective of whether the term “obtained”, “obtainable”, “directly obtained” or an equivalent wording is used (Kirin-Amgen Inc v Hoechst Marion Roussel Ltd [2005] RPC affirming EPO law, i.e., Decision T 150/82 International Flavors and Fragrances Inc. [1984] 7 OJEPO 309). Such a claim lacks novelty if a prior art product, even if made by an undisclosed process, appears to be the same as, or indistinguishable from, the claimed product. The patentability of a product defined by a product-by-process claim does not depend on its method of production. Therefore, a product is not rendered novel merely by the fact that it is produced by means of a new process.

2.73 However, where a product cannot be satisfactorily characterized with reference to its structure, composition, properties or other means (such as when the structure or composition of a product is unknown), it might be allowable to claim the product using a product-by-process claim. During examination, such a claim should be construed as a claim to the product per se that possesses the characteristics derived from the manufacturing process as stated in the claim. For example, when a claim recites “a twolayer structured panel which is made by welding together an iron sub-panel and a nickel sub-panel.”, the process of “welding” would be considered by the examiner in assessing patentability over the prior art since the process of welding produces physical properties in the end product which are different from those produced by processes other than welding; that is, the product can only be defined by the process step. Novelty of the claim is not brought into question unless an identical two-layer structural panel made by means of welding is discovered in the prior art.

2.74 Where a product that can be accurately described by referring to its structure, composition or means other than its method of preparation or production, but is defined using a product-by-process claim, the Examiner may raise a clarity objection. If there is another claim to the identical product in the application, then the productby-process claim may also lack conciseness as the two product claims might have an identical scope of protection. In order to overcome said objections, the applicant should provide evidence to the contrary.