High Court thrusts proving patent's invalidity on the infringer

High Court thrusts proving patent's invalidity on the infringer

The standard has to be met when applying the principle of 'credibility'

The Delhi High Court has ruled that when an infringer seeks to defend patent infringement on the ground that the patent is invalid, the onus to prove the invalidity lies heavily on them. This standard has to be met when applying the principle of "credibility".

The observation came from Justice C Hari Shankar as he restrained Natco Pharma Limited from importing, selling, offering for sale, exporting, or dealing directly or indirectly in Active Pharmaceutical Ingredient (API) containing Eltrombopag Olamine (EO).

(EO is a compound, which helps in enhancing platelet production and is particularly used in the treatment of low blood platelet count, referred to as thrombocytopenia).

The patent for EO was reckoned in 2003 and it would remain alive for 20 years. The invention was granted non-proprietary United States Adopted Name (USAN) "Eltrombopag Olamine". The patent owned by Novartis is marketed by it under the trade name "Revolade".

The court was told that Natco Pharma was launching its brand of EO in the market. Novartis argued, claiming that Natco Pharma had not obtained any license from it.

The court observed that prima facie there appeared to be a fundamental misconception relating to the concepts of a "credible challenge" and "vulnerability." The submission advanced by the defendant was predicated on the premise that the slightest shadow of doubt, which could be cast on the patent, was sufficient to constitute a credible challenge. It exposed the vulnerability to revocation and the proposition was completely misconceived.

Justice Shankar added that even if a ground was made for revocation of a patent, it could not be done automatically. It remained a matter of discretion of the patent authority.

The judgment said, "The grant of such discretion is itself a pointer to the legislative intent that, before revoking a patent, the authority is required to satisfy itself that all considerations have been made and revocation is absolutely necessary.

"It is only when, judged on that standard, a credible challenge to the validity of the patent as vulnerable to revocation is made out, that an infringer can escape the consequence of infringement. Thus, the standard is rather high, than low."

The court said that the infringer never chose to challenge the suit patent either at the pre-grant or the post-grant stage. That meant it had not "cleared the way" before exploiting the suit patent.

"Only when it was "caught in the act", the defendant sought to question the validity of the suit patent," the court added.