Importance of expert testimony in patent cases

By DPS Parmar, LexOrbis

The grant of a patent invariably follows a thorough examination by expert patent examiners of the patent offices. In some jurisdictions, this grant carries with it the presumption of validity. In India, however, the validity of a patent is not guaranteed by the grant according to section 13(4) of the Patents Act, 1970. When the grant of a patent is challenged it requires evidence to prove the grounds of invalidity taken by the opponent. Most of these patent invalidity challenges, by nature of being technical, require opinions of expert witnesses.

The Intellectual Property Appellate Board (IPAB), in a number of cases, have remanded the cases back to the controller on this ground alone. Non-consideration of expert evidence was treated as a violation of the principle of natural justice. Appeal courts are harsh to the decisions taken by lower courts, or IPAB, or controllers without appreciating expert evidence.

Judges’ discretion

patent dispute
DPS Parmar
Special counsel

The usefulness, scope and extent of technical expert testimony in the patent disputes will be tested in future cases. As we are still in the process of evolving the precedence on role of experts in patent disputes, it will take some time for intellectual property litigators to break the shackles placed on trial courts on whether an expert view is essential. As stated by American judge Learned Hand in Kohn v Eimer, “We have not the slightest wish to minimize the vital importance of expert testimony in patent suits, or to suggest that we are not absolutely dependent upon it within its proper scope; but that scope is often altogether misapprehended … when the judge has understood the specifications, he cannot avoid the responsibility of deciding himself all questions of infringement and anticipation, and the testimony of experts on these issues is inevitably a burdensome impertinence.”

When is it essential?

In the recent Renadyl (formerly known as Kbow Biotics) appeal case, Madras High court stressed the need for expert evidence in support of the petition for the revocation of a patent. The court held: “The petitioner has not produced any evidence of an expert before the third respondent appellate board to substantiate its plea that the invention is a mere “admixture” or that the patent was liable to be revoked on the grounds stated in the petition filed by it”.

To appreciate the evidence filed in support of the petition for revocation of the patent, the petitioner should have played a proactive role by either producing an expert or an expert’s affidavit and, if necessary, such expert could have been subjected to cross-examination … If it was found that the petitioner had made out a case on merits, the third respondent appellate board could have also called for an expert’s view under section 115 of the act. However, it is obvious the petitioner miserably failed to even establish a prima facie case on the strength of the materials placed by it before the third respondent appellate board.”

The court in this context also questioned the IPAB fact-finding approach without the expert evidence.

In another longstanding dispute, the genetically modified Bollgard-II Bt cotton seed appeal case, the Supreme Court questioned summary disposal of the case by the division bench and firmly established the importance of expert evidence. The court ruled that: “We are, therefore, satisfied that the division bench ought not to have disposed of the suit in a summary manner by relying on documents only, extracted from the public domain, and not even filed as exhibits in the suit, much less examination of expert witnesses, in the facts of the present case. There is no denying that the issues raised were complicated requiring technological and expert evidence with regard to issues of chemical process, biochemical, biotechnical and microbiological processes and more importantly whether the nucleic acid sequence trait once inserted could be removed from that variety or not and whether the patented DNA sequence was a plant or a part of a plant, etc. are again all matters which were required to be considered at the final hearing of the suit.”

Questioning use of experts

Earlier, in Sri Rajesh Kumar Banka v Union Of India & Ors, decided by Calcutta High Court, the opinion of Justice IP Mukerji set the tone on how IPAB should utilize expert evidence. He observed: “Even if the petitioner had not asked for cross-examination of the witness, the board, comprising experienced adjudicators, ought to have extended the liberty of cross-examination to the petitioner to evince the truth.”

Justice Mukerji questioned the competency of the IPAB when he observed that, “The court should not turn into an expert in areas in which it has no competence.”

(This is the first of a two-part series. The second part will be published in the next issue of India Business Law Journal.)

DPS Parmar is a special counsel with LexOrbis’s IPAB practice group.

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