Introduction
At the heart of a patent application lies its claims. A claim is a signifier of the scope of protection that is sought under the patent. Claims are the first and most important aspect to be examined during prosecution, infringement, and litigation. Every patent application must be accompanied by at least one claim, and usually, an application contains several more.
The language used by patent claims is usually very clear and precise, and consists of words that have been interpreted and defined over decades by courts and patent offices. Seemingly innocuous practices such as the use of a synonym, the position of a conjunction, or the choice of a plural, can all be extremely contentious issues in patent infringement suits.
Two-part claims
Patent claim structures are, for the most part, harmonized across patent offices in different countries. However, a few patent offices prefer certain claim formats, one such being the two-part form. Two-part claiming requires that the claim be sectioned into two parts, the parts separated by the transitional phrase "characterized in that", or "characterized by". The general interpretation of such claims is that the section prior to this phrase) describes the state-of-the-art or the prior art, while the post-characterizing portion describes the inventive component of the invention. This note briefly examines two-part claiming practices in different jurisdictions and concludes with best practices for applicants in India.
Europe
The two-part claim is preferred in Europe (EP) as the default format for claims, with Rule 43(1) of the European Patent Convention (EPC) stating that:
"Wherever appropriate, claims shall contain: (a) a statement indicating the designation of the subject-matter of the invention and those technical features which are necessary for the definition of the claimed subject-matter but which, in combination, form part of the prior art; (b) a characterizing portion, beginning with the expression "characterized in that" or "characterised by" and specifying the technical features for which, in combination with the features stated under sub-paragraph (a), protection is sought".
The Guidelines for Examination in the European Patent Office ("the Guidelines") explain this requirement further: the pre-characterizing portion must contain a general statement of the subject matter of the invention and 'those technical features which are necessary for the definition of the claimed subject-matter but which, in combination, are part of the prior art". Thus, this pre-characterization portion should claim the state-of-the art, or the non-inventive features of the invention. On the other hand, the post-characterizing section must claim the inventive technical features of the invention which in combination with the non-inventive features define the scope of the claimed invention.
However, EP does permit fluidity in claim structure. Under the Guidelines, one-part claiming is deemed appropriate wherever strict demarcation into two-parts is likely to cause confusion and ambiguity in the claim. For instance, the Board of Appeals, in T0170/84, concluded that while Rule 29(1) (presently Rule 43(1)) of the EPC) requires that a claim should be formulated in two-part form, when read with Article 84, the two-part form is not appropriate if it would lead to a "complex formulation" of the claim and compromise the clarity of the claim.
United States
The US equivalent of the two-part claim is the "Jepson" claim. Unlike EP, it is not the default format for claims, and is recommended only in special circumstances. This specific claim format describes an improvement over the prior art. 37 C.F.R. 1.75(e) describes such claims thus:
'(Where the nature of the case admits, as in the case of an improvement, any independent claim should contain in the following order: "(1) A preamble comprising a general description of all the elements or steps of the claimed combination which are conventional or known, (2) A phrase such as "wherein the improvement comprises," and (3) Those elements, steps, and/or relationships which constitute that portion of the claimed combination which the applicant considers as the new or improved portion".
The interpretation of such claims veers on the restrictive side, as the US Manual of Patent Examining Procedure (MPEP) 2129 specifies that: "Drafting a claim in Jepson format . is taken as an implied admission that the subject matter of the preamble is the prior art work of another".
India
In India, two-part claiming is not a prescribed claim format, and in contrast to EP and the US, no specific provisions are described in the Indian Patents Act, 1970 ("the Act"), for such claims. Instead, Section 10(4)(c) of the Act merely requires that:
"Every complete specification shall end with a claim or claims defining the scope of the invention for which protection is claimed".
Section 10(5) adds that, "The claim or claims of a complete specification shall relate to a single invention..shall be clear and succinct and shall be fairly based on the matter disclosed in the specification".
However, two-claim formats are a prevalent practice in India, and some guidance for this can be found in the Manual of Patent Office Practice and Procedure ('the Manual'). Section 05.03.16(n) of the Manual states:
"If the invention is an improvement on a product or a process existing in the prior art, the invention should be distinguished very clearly by characterizing the claim with respect to the prior art. In such cases, the claim will have two parts separated by the word 'characterized by' or 'wherein''.
The concept of a two-part claim is reiterated in Section 05.03.16(o) of the Manual, which lays down the distinguishing features of the first claim, also known as the "Principal Claim":
"The first claim is always an independent claim also known as 'Principal Claim'...The claim may be properly characterized with respect to the 'prior art', defining all the technical features essential to the invention or inventive concept. The claim should bring out sufficient details of interrelationship, operation or utility to establish that the invention achieves the intended objectives".
Prosecuting and defending two-part claims in India
In practice, while there is no specific mandate to draft claims in this format, the Indian Patent Office often requires that claims be amended into the two-part format during the examination of a patent application.
But applicants are generally wary of locking themselves into such claim formats. This is because two-part claims risk a narrow and restrictive interpretation. For instance, in Enercon India Pvt. Ltd. Vs Aloys Wobben [ORA No. 5/2009 dated 18 November 2010; ORA No. 27/2009 dated 2 December 2010, and ORA No. 38/2009 dated 2 December 2010], the Intellectual Property Appellate Board relied on both Article 43(1), EPC and Jepson claims from the US, to conclude that the inventive step lies in post-characterization part of a claim.
In most instances, applicants can successfully argue against the characterization of claims into two-part formats on grounds of lack of clarity, i.e., by arguing that it would result in a confusing claim or that the combination/inter-relationship of the features are such that the inventive step is an outcome of the combination.
Conclusion
Two-part claiming is a format employed in multiple jurisdictions, including Europe, the US and India, but the format varies in detail, relevance, and interpretation in these jurisdictions. While this format is regarded as the default in Europe, in the US, it is used only in special cases. India does not statutorily prescribe the use of such claims at all, but in practice, the Indian Patent Office nudges applicants to redraft claims thus. However, converting claims into the two-part format can be avoided in India if the clarity of the claims is compromised. It is also generally recommended to avoid characterization of claims to prevent a possible restrictive interpretation of the claims by Indian courts.
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.
