India: Means Plus Function Claims Dilemma And CRI Guidelines

Last Updated: 31 January 2018
Article by DPS Parmar

In the computer related inventions we invariably come across the terms in the claims such as "means for" or "step for" followed by the function they perform. These types of claims are different from traditional set of claims as they do not recite any structural features to carry out the invention. The question of determining the allowability of patent claims written in "means-plus-function" style, always posed difficulties in the examination in IPO. The drafting of the claims of an invention based on the functionality rather than reciting employed structural features within the body of the claim itself is very common in the computer implemented inventions particularly involving software. Such drafting of claims is fine so long as the specification clearly define the means employed to perform the invention. But in IPO such claims are invariably subjected to rigorous examination. Let us examine the position of such claims in the Indian context and there allowability under the Patents Act, 1970.

No Statutory Provisions on Means plus function claims

We do not find any provision in Indian patent act which explicitly deals with means plus function style of claims. Thus there is no statuary bar on drafting of the claims in this manner. Only restriction and requirement in respect of drafting of such type of claims which is applicable to all inventions is found in Section 10(4) (4) where it is stated that 'Every complete specification shall— ..... (c) end with a claim or claims defining the scope of the invention for which protection is claimed.'

This clearly indicates that the terms used in the claims must be definitive and supported by the description in complete specification. There is nothing intrinsically wrong with the "means-plus-function" style claim language but the examiners in IPO prefer to deal with tangible structure while examining such cases. They insist on to bring structural limitations in the claims and raise the objections of indefiniteness of the terms used such as 'means for' or 'step for'.

Need for structural limitation?

In order to overcome this objection the applicants are at times compelled to

limit the claims further to include the structure necessary to perform the recited function. This approach of the Examiners stems from the very nature of this type of claims where the claim recites a feature by what it does rather than by what it is. Such type of functional claiming is viewed cautiously by patent examiners when they found that it merely describe a problem to be solved or a function or result achieved by the invention. Invariably lack of definiteness objection under section 10(4)(4)(c) is raised as such claims are viewed as the category of invention where the boundaries of the claim scope may perhaps be either unclear or too board to encompass all known or unknown means or steps.

Pre CRI position

There was nothing wrong with the "means-plus-function" style claim language before the CRI guideline and in fact the Indian Patent Office had been granting "means plus function claims". It is noteworthy that many patents on means plus functions claims were granted even if the structural features of those means are not disclosed in the specification. For example patent No. 229632, 234157, 240471, and 241747. These 'mean plus function' claims cases were deliberately handpicked for the reason that these cases were under litigation and no objection to the validity was raised due to fact that the claims are styled as 'means plus function'. Hon'ble High court has rather upheld validity of such claims of these patents. Thus, the grant of 'means plus function' style claims is legitimate under the Indian patent law. But after the new CRI guidelines were issued the examiners in IPO prefer to raise objection of indefiniteness perhaps just to get clear scope of coverage of the claimed invention while examining such cases or just to limit the scope of the claims coverage.

Post CRI - paradigm shift

The position of IPO made a paradigm shift on 'means plus functional' type claims after the issue of new CRI guideline in 2016 and 2017 specially in view of para 4.4.5 where it is stated that 'The 'means' mentioned in the claims shall clearly be defined with the help of physical constructional features and their reference numerals to enhance the intelligibility of the claims.' The IPO examiners have now started to insist on to bring structural limitations in the claims and raised the objections of indefiniteness where terms such as 'means for' or 'step for' are used in recited claims. In order to overcome this objection the applicants are at times compelled to limit the claims further to include the structure necessary to perform the recited function. In the same breath however, the recent CRI guidelines in para 4.4.5 also guided the examiner not to insist on the structural feature limitations in the claims itself and rather look for the definitions in the specification that clearly define the means employed to perform the invention. The examiner thus found him caught in the two opposite positions. There is no explicit or implicit legal or statutory support for such a condition to be insisted upon by the examiner where he found that the claims are drafted in "means plus function" style.

Examiners Dilemma - unfettered discretion

The IPO examiner dilemma is further aggravated as there is no statutory definition to ascertain that which claims are 'means plus function' type leaving the examiner to look certain terms similar to that stated in the CRI guidelines such as 'The claims concerning CRIs are often phrased in means for performing some function such as means for converting digital to analog signal etc.' CRI Guidelines issued so far however, does not come to the rescue of the Indian patent Examiner in respect of how to identify the means plus function claims. This leaves the examiner with lot of discretion to raise the objection of indefiniteness of the terms used in the means plus function type of claims. In order to identify means plus function claims IPO Examiners invariably grapple with and look for key words or phrases such as "configured to", "permitting...", "programmable means for," "capable of engaging," "adapted to," "," "operable to...", "mechanism", "data processing system" "mechanism for," "module for," "device for," "unit for," "component for," "element for," "member for," "apparatus for," "machine for," or "system for." and so on recited in the claims apart from only example given in the CRI guideline i.e. 'as means for converting digital to analog signal etc.'

Computer programme and software determinants

Once the Examiner identified that claims are drafted in the means plus function style the CRI guidelines seeks examiner to further to look for information relating to implementation of the invention in the specification and if the specification supports implementation of the invention solely by the computer program then such means plus function claims may be deemed as only computer programme per se falling within the ambit of non-patentable subject matter under section 3(k). Moreover, though act does not refer the term software, the CRI guidelines directed to keep such software within the scope of non-patentable subject under section 3(k) as seen from the last para of this guideline for "mean plus function claims" where it is stated that "Where no structural features of those means are disclosed in the specification and specification supports implementation of the invention solely by the software then in that case means in the "means plus function" claims are nothing but software."

Impact of Ergo Licensing and Noah Systems

At stated above this new approach to follow by the examiner has no legal basis nor supported by any Indian court precedent. There is no support, either in the actual legal precedents/holdings in prior cases or in the statute for the proposition put forward in the CRI guidelines that functional language in the claims would renders a claim falling under section (3k).These guidelines are not binding on the examiner and Controller yet the Indian Patent Office off late has started raising objection especially in relation to computer related inventions perhaps due to Federal court decision in Ergo Licensing and Noah Systems in US.

In Ergo Licensing, certain means plus function claims of US 5,507,412 ('412 patent) relating to an infusion system were called for consideration of definiteness for alleged infringement by CareFusion. Defending the case the Carefusion raised the issue of indefiniteness. Federal court Affirm the findings of the district court that the terms "control means" and "programmable control means" are indefinite" and "Because the district court correctly held that no corresponding structure is disclosed in the specification."

In Noah Systems the US 5,875,435 patent was for an automated financial accounting system and the system allows a business or individual to connect to the computers of companies with which that entity conducts business so that information regarding financial transactions can be transmitted between them. Noah asserts that Intuit's Quicken and QuickBooks products infringe system claims 12–17, 29–38, and 40–56. All of the asserted claims contain an "access means" limitation. After construing the disputed terms an "access means" the district court determined that limitation in the claims of the '435 patent was indefinite, and, therefore, granted Intuit's Motion for Summary Judgment of Invalidity. Federal court "affirmed the findings" stating that .. "Because we agree that the "access means" limitation is indefinite, we affirm the district court's judgment."

It would be too early to predict whether IPO would follow US approach in deciding the 'means plus function' CRI cases and decide indefiniteness based on the description in the speciation as done by US courts or grant the patents based on the presence of structure limitation in the claims. Trends towards the later approach are evident from the objections received for inclusion of structural features in the claims.

US Approach –means plus function claims

Contrary of Indian stand provisions of U.S.C §112 (f) of Code Title 35 - Patents , did not prohibit functional claims. According to US law —'An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof''. In Indian law there no such similar provision. If we look at history of the functional claims in US it all started way back in middle of Nineteenth century when the inventors drafted the claims to identify the inventive contribution and/or market replacements rather than merely describing and claiming a device. Using this approach most of the CRI inventions are now defined in functional terms. The first functional claim which was rejected than in US was relating to Halliburton Oil Well Cementing Co. v. Walker, 329 U.S. 1 (1946) where 'Means for measuring the location of obstructions in wells' was under the dispute and Claim 1 read as follows:

"In an apparatus for determining the location of an obstruction in a well having therein a string of assembling tubing sections interconnected with each other by coupling collars, means communicating with said well for creating a pressure impulse in said well, echo-receiving means including a pressure responsive device exposed to said well for receiving pressure impulses from the well and for measuring the lapse of time between the creation of the impulse and the arrival at said receiving means of the echo from said obstruction, and means associated with said pressure responsive device for tuning said receiving means to the frequency of echoes from the tubing collars of said tubing sections to clearly distinguish the echoes from said couplings from each other."

The claimed means in terms of a means plus functional terms in Halliburton Oil Well Cementing Co. v. Walker, 329 U.S. 1 (1946) were rejected as court found the claims failed adequately to depict the structure, mode, and operation of the parts in combination. This judgement rest on the observation made by the court while rejecting these functional claims that

"No one of these claims describes the physical relation of the Walker addition to the old Lehr and Wyatt machine. No one of these claims describes the manner in which the Walker addition will operate together with the old Lehr and Wyatt machine so as to make the "new" unitary apparatus perform its designed function. Thus, the claims failed adequately to depict the structure, mode, and operation of the parts in combination."

According to the court "The language of the claim thus describes this most crucial element in the "new" combination in terms of what it will do, rather than in terms of its own physical characteristics or its arrangement in the new combination apparatus.

The court observed that

"Under these circumstances, the broadness, ambiguity, and overhanging threat of the functional claim of Walker become apparent. What he claimed in the court below and what he claims here, is that his patent bars anyone from using in an oil well any device heretofore or hereafter invented which combined with the Lehr and Wyatt machine performs the function of clearly and distinctly catching and recording echoes from tubing joints with regularity . Just how many different devices there are of various kinds and characters which would serve to emphasize these echoes we do not know. The Halliburton device, alleged to infringe, employs an electric filter for this purpose. In this age of technological development, there may be many other devices beyond our present information -- or, indeed, our imagination -- which will perform that function and yet fit these claims. And, unless frightened from the course of experimentation by broad functional claims like these, inventive genius may evolve many more devices to accomplish the same purpose. The court also reasoned that "Yet, if Walker's blanket claims be valid, no device to clarify echo waves, now known or hereafter invented, whether the device be an actual equivalent of Walker's ingredient or not, could be used in a combination such as this, during the life of Walker's patent." [Emphasis added]

To cut the story short many such type of claims were not allowed in US after Halliburton decision till 1952.

Return of Functional claims

Year 1952 again saw the acceptability of the functional claims by USPTO after introduction of the revised 35 U.S.C §112 (f) under certain conditions. The new provision stipulated that —"An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof." US position relating to functional claims since then have not been changed as this clause has not been amended since its passage. Moreover, in In re Swinehart, 439 F.2d 210, 213, (CCPA 1971) court reaffirmed that a patent applicant is free to recite features of an apparatus either structurally or functionally. After passage of the Patent Act of 1952, the courts began to allow not only means-plus function claims, but also allowed inventions to be claimed by their functions, regardless of the underlying technology. It is pertinent to note that in India this Para 4 limitation is applicable to the CRI only and not to any other technology. We must see that guidelines are crafted for general application of statutes and not industry specific. If this happens it vests significant power with patent examiner to limit legitimate patentable subject matter. Line drawn by these guidelines is a futile exercise as one can still draft claims in a CRI applications so as to remain out of the predefined category.


The para 4 of the CRI guidelines is not dealing with the patentability of the subject matter under section 3(k) rather it is about the style in which claims are structured and drafted. Clearly, no restriction is placed on the means plus function style of claim drafting but the limitation of disclosure in the specification are brought into play to define the terms used in the claims. Here examiner is left with his own understanding to limit a means plus function element to the particular technologies described in the specification and the equivalents thereof. This leaves enough elbow space to allow such claims to pass the muster of definiteness if persons of ordinary skill in the art reading the specification understand the term to be named for the structure that performs the function, even when the term covers a broad class of structures or identifies the structures by their function. In any case CRI guideline do not demand that term used in claim is required to denote a specific structure or a precise physical structure. We must understand that rules for examining means plus function cases for CRI cannot stand on different footing as in mechanical and other related cases. Just because the subject matter exclusion is the only difference between software patents and other patents we can not necessarily assume that software patents are subject to a different disclosure requirement.

Lastly how para 4 of CRI guidelines would responds to illusory problems of indefiniteness and over-breadth of software patents by using a archaic mechanism that no longer fits with the modem claim construction regime only time can tell. It is pertinent to note that patentees could use the grant of rights covering a single component of a complex program to prevent any "making" or "using" of the program as a whole under section 48. But how the courts will decide such litigation let's wait and see. Last but not the least how many software patents one gets depends in part on how one defines a software patent to pass the muster of examination of indefiniteness.

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.

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