Patents are not just instruments of private commercial utilisation but also have an impact on public policy. They are thus, governed by a system which allows for challenge to the validity of a patent at different stages.

Before the Patent Office, the Act provides for ‘pre-grant opposition’ under S. 25(1) against patent applications as well as ‘post-grant opposition’ against granted patents within one year from publication of grant of patent. Grounds are identical for the above two stages.

Further, the Act provides for Revocation of Patents, under Section 64 by the Intellectual Property Appellate Board (IPAB), anytime within the entire term of the patent, or in a suit for infringement by the High Court.

The issue here is with regard to level of proof for ‘obviousness’ or lack of inventive step1 which is available as a ground of invalidity in both S.25 and S.64. In an opposition the ground is available under S.25(1)(e) (for pre-grant) or S.25(2)(e) (for post grant) which reads as ‘that the invention so far claimed in any claim of the complete specification is obvious and clearly does not involve an inventive step, having regard to the matter published as mentioned in clause (b) or having regard to what was used in India before the priority date of the applicant’s claim.’ On the other hand, the ground for revocation before IPAB based on lack of inventive step has been provided in Section 64(1)(f) which reads ‘that the invention so far as claimed in any claim of the complete specification is obvious or does not involve inventive step, having regard to what was publicly known or publicly used in India or what was published in India or elsewhere before the priority date of the claim.

It can be seen that the basis of the enquiry of obviousness either in opposition or revocation is similar i.e. prior publication, prior knowledge or prior use. However, one difference between the provisions is that the word ‘clearly’ appears in Section 25(1)(e) and 25(2)(e) whereas the same is not present in Section 64(1)(f) for revocation. Thus, this article deals with the issue as to whether the burden of proof to show obviousness in an opposition is higher than that required in revocation under Section 64.

As per the interpretation of statutes, a statute is an edict of the Legislature2. When the words of a statute are clear, plain or unambiguous, i.e., they are reasonably susceptible to only one meaning; the courts are bound to give effect to that meaning irrespective of consequences3. In other words, the presumption is that words as they appear in the statute must be given a meaning and the presumption is that legislature does not use words frivolously. The contrast observed in the language of statutes under Section 25 (1) (e) and Section 64 (1) (f) is the adverb ‘clearly’, which appears in the former but not in the latter. Therefore, one must construe and act upon the word used in the said provision i.e. the use of ‘clearly’.

The dictionary meaning of ‘clearly’ is ‘without doubt’4. It also means ‘in a way that is certain’5. Presence of the word ‘clearly’ in S.25 shows that while a challenger is required to show lack of inventive step ‘without doubt’ before the Controller, the same is not required before the IPAB. This is not to suggest that there has to be ‘proof beyond reasonable doubt’ but it is worth examining as to whether the legislature intended something higher than ‘preponderance of evidence’ requirement which is generally applicable in civil proceedings. It is also relevant to note that the Controller/Patent Office does not have a judicial background, whereas the IPAB necessarily has a judicial member as well as the Court while exercising jurisdiction under Section 64. Thus, obviousness being a mixed question of fact and law, this article examines whether the Controller would need a higher level of proof as compared to IPAB / Court to uphold the ground of obviousness.

A similar issue was dealt with in a judgment of the Court of Appeal, UK in 1964, where the General Electric Co (Patent, subject matter)6, made an application before the Patent Office, London for grant of patent for improvements in polyester resins and for improvements relating to electric conductors insulated with polyesters. The Application was opposed by Dr. Beck & Company, G.m.b.H, under Section 14(1)(e) of the Patents Act, 1949 (the UK Act) on the ground that ‘the inventions claimed in any respective claims of the complete specification where obvious and clearly does not involve an inventive step, having regard to the matter published in the United Kingdom before the priority date of the applicant’s claim’. The UK Patent Office held that the invention was obvious and clearly did not involve any inventive step. The Applicant eventually appealed to the Court of Appeal disputing the level of evidence considered while rejecting its case.

In the judgment, Lord Justice Diplok observed that the Applicant desired to raise a question of general principle as to the effect of Section 14(1)(e) of the UK Act, and as to the duty of the Comptroller when exercising his jurisdiction to determine whether or not to refuse a patent when grant is opposed on such ground. Lord Diplok observed that Section 14(1)(e) of the UK Act is to be contrasted with a similar ground under Section 32 (1)(f) of the UK Act, which provided for revocation of patent, on similar terms, but omitted the adverb ‘clearly’.

Even while explaining the difference in character of proceedings, the Court found that in an opposition to the grant of patent, the Comptroller has the power under the law to take written and oral evidences but parties have a right to insist upon cross examination. The court was informed that in practice oral evidence was seldom taken unless ordered by Comptroller. Further, there were no options for parties to appeal without leave. In contrast the revocation would take an ordinary course of action before a court of law involving oral evidence and right to appeal.

In view of the above, the Court thus, held that the Comptroller’s ‘jurisdiction to refuse a patent for lack of inventive step should be exercised only in ‘clear’ cases. This does not mean that it should only be exercised in cases which are on the face of them simple cases.’ It was further held that the right principle is that if there is conflict of fact or credible expert opinion on a question on which the obviousness ground depends, the Comptroller should not exercise jurisdiction to refuse unless after cross-examination the conflict is resolved in favour of the opponent. In the case at hand, the Court found that there was no apparent conflict on such facts or evidence thereby finding no reason to interfere with the decision of the Patent Office on obviousness.

In conclusion, if we were to apply the above case to the Indian Patent Act, we may note striking similarities between the Indian scenario of today and the system under the UK Act of 1949. While the Indian patent Controller may have the power under S.77 to call for oral evidence, there is no right of the parties under the Act to insist on this. On the other hand, in a revocation proceeding before the IPAB cross examination has been held to be a matter of right7. Needless to say revocation before a Court would always entail oral testimony with right to appeal. Thus, it is manifest that a Controller must exercise its discretion under S.25 to refuse a patent on obviousness only if it is ‘clearly’ borne out from the evidence adduced by the parties that the invention does not involve any inventive step.