The Delhi High Court (DHC) has recently granted an injunction  to FMC Corporation (“the plaintiff”), against the defendant Natco Pharma Ltd and Best Crop Science LLP (“the Defendants”).

The court has held that pending disposal of the suit, the defendant is restrained from manufacturing, using, selling, distributing, advertising, exporting, offering for sale or in any other manner, directly or indirectly, dealing in any product which infringes the subject matter of the product patent IN 201307 (IN’307), including the product Chlorantraniliprole (CTPR), claimed therein, and (ii) using, directly or indirectly, any of the process as claimed in IN 213332 (IN’332), for the manufacture of Chlorantraniliprole, or the claimed subject matter of IN 201307.

Background

The Markush structure, along with the necessary radicals to be substituted therein, the method of preparation and the actual and precise molecular structure and formula of CTPR, is specifically claimed in the suit patent IN’307. CTPR is, additionally, one of 148 compounds specifically exemplified in the suit patent.  No pre-grant or post-grant opposition, to IN’307, was filed by anyone, including the defendant. Counterparts of the suit patent had been granted in more than 40 countries, in all of which they continue to subsist till date, Colombia being the sole jurisdiction where the equivalent of the suit patent was invalidated. IN’332, which is the process patent. No pre-grant or post-grant opposition was filed in relation to IN’332. Moreover, the counterparts of IN’332 had been granted patents in over 40 countries, in none of which have they been revoked or invalidated.

IN 204978 (IN’978) contains a Markush formula, from which the compounds in Formula 1 of IN’307 are asserted to be a novel and inventive selection. The plaint acknowledges that CTPR falls within the scope of the numerous compounds, and is in the class of anthranilamides, included in the Markush formula, disclosed and claimed in the patent IN’978, but asserts, with equal emphasis, that CTPR is not specifically disclosed in IN’978 and that no person skilled in the art would be able to synthesise CTPR based on the claim and disclosure in IN’978.

Test results are also provided to compare the compounds claimed and disclosed in IN’307, with their closest counterparts disclosed in IN’978. These tests indicated superior insecticidal activity of the compounds disclosed in IN’307 visà-vis their closest counterpart

While granting an injunction, the court held that the Defendants failed to establish prima-facie invalidity of the granted claims, which is the main defence of the defendants.

Some important findings/observations made by the Court while coming to the above conclusion are discussed in brief below:-

Presumptive validity of a granted patent – Section 13(4)

The court held that there is an obvious etymological difference between a “guarantee of validity” and a “presumption of validity”. Grant of patent cannot, obviously, guarantee its validity; else, a granted patent would become immune from challenge. Thus, the challenge, posed by the defendant to the validity of the plaintiff’s patent need not be such as to demonstrate, conclusively, the invalidity thereof.

The court held that at the interim stage, it is sufficient if the defendant is able to make out a case of the suit patent being vulnerable to revocation under the Patents Act. This vulnerability has, however, to be demonstrated by way of a credible challenge. The onus would be on the defendant, therefore, to establish the credibility of the challenge raised by it. The challenge cannot be incredible, fanciful, or moonshine.

Genus /species argument

The defendants raised three contentions to support the submission that CTPR was disclosed by the genus patent, i.e., Claim 22 in IN’978.

• that Section 11(2)(b) of the Patents Act creates a presumption of the existence of a disclosure in a patent to which the priority date has been assigned,

The court did not agree with the same and held that once the defendant accepts that Markush claims are patentable, it no longer remains open to the defendant to rely on Section 11(2)(b) to advance an argument that, as Claim 22 in IN’978 was patented, there must be a presumption of disclosure of CTPR therein. The Court agrees with the plaintiff’s assertion that Claim 22 in IN’978 claimed a Markush structure, which does not claim, teach or disclose CTPR, or the Markush structure claimed in Claim 1 of IN’307, even if CTPR may come within the coverage of Claim 22 in IN’978.

• that the plaintiff had admitted, in the plaint, “coverage” of CTPR by the genus patent, and the Supreme Court, in Novartis AG v. U.O.I  has clearly held that there can be no dichotomy, or distinction, between “coverage” and “disclosure” in a patent; ergo, acknowledgement of coverage amounts to an acknowledgement of disclosure,

The court in this regard held that:-

• According to the Supreme, any dichotomy, sought to be drawn between coverage or claim, and disclosure or enablement or teaching, in a patent, struck at the very root of the rationale of patent law. Obviously, the Supreme Court has disapproved, in no uncertain terms, of any dichotomy being sought to be drawn between coverage and disclosure. Having said that, etymologically, “dichotomy” is not the same as “distinction”. The Supreme Court has not held that coverage and disclosure are the same. Nor has it held that there is no distinction between coverage and disclosure. Choosing its words with precision, the Supreme Court has held that there is no “dichotomy” between “coverage” and disclosure”. “Dichotomy” is defined, in the Oxford Dictionary, as “a division or contrast between two things that are or are being represented as being opposed or entirely different”. In holding that there can be no dichotomy between coverage or claim, on the one hand, and disclosure or enablement or teaching, on the other, the Supreme Court has not, therefore, held that they are identical. Apparently, in fact, the Supreme Court has, in disapproving the existence of any “wide gap” between coverage and disclosure, clarified that it merely disapproved of any dichotomy between these concepts, and was not seeking to hold that the concepts were identical. Indeed, the judgement of the Supreme Court, read thus, would be in entire accord with the covenants of the Patents Act, which make repeated reference, in more than one provision, to “disclosure”. Clearly, the framers of the Patents Act did not envisage the “claim” or “coverage” of the claim, to be identical to “disclosure”. Nor, for that matter, has the Supreme Court so held.

• The court also stated that in the present case, there is no claim, and no disclosure, by the plaintiff, of CTPR in the genus patent, i.e. Claim 22 of IN’978. Therefore, no question of any dichotomy between claim and disclosure, therefore, arises in the present case.

• that, in fact, the preferred embodiments, forming part of the Complete Specification of Claim 22 in IN’978, when applied to the Markush structure claimed therein, “led to CTPR”.

The court in this regard held that:-

• From a bare glance, it is apparent that the defendant has cherry picked the substitutions’, as well as the radicals for substitutions at the various places on 5-membered or 6-membered heteroaromatic rings, out of the multifarious choices provided in Claim 22 in IN’978, so as to arrive at CTPR, or the Markush structure in Claim 1 in IN’307. No explanation for selecting these particular substitutions, out of the several substitutions provided in the Markush claim in IN’978, is forthcoming in the pleadings. It is apparent that these substitutions have been carefully selected so as to arrive at the Markush structure claimed in Claim 1 in IN’307, or at CTPR
• From the teachings in the genus patent, the person skilled in the art must be in a position to arrive, without unduly straining his imaginative and creative faculties, at the specie patent, in order for the specie patent to be invalidated on the ground of obviousness. The element of “directness” must be there. The choice which the person skilled in the art would make, by way of substitutions on the Markush moiety or otherwise, must be apparent from the teachings in the genus patent, in order for the specie patent to be treated as “obvious”
• Prima facie, a person skilled in the art would not selectively choose the substitutions unless she, or he, is aware of the fact that, ultimately, CTPR is to be produced. No such effort having been made for all the years during which IN’978 remained valid, and the plaintiff being the first to synthesise CTPR from the Markush moiety claim then disclosed in Claim 22 in IN’978, it is not possible to accept that the embodiments provided in Claim 22 in IN’978 would “lead” a person skilled in the art to CTPR. No teaching, so as to enable such a person to synthesise CTPR can, therefore, be said, prima facie, to exist in the disclosure provided in Claim 22 in IN’978

Prior claiming – Section 64(1)(a)

The defendant in the present case, in asserting vulnerability of IN’307 as having been anticipated by prior claiming in Claim 22 of IN’978.

The court held that Section 64(1)(a) provides, as a ground for revoking a patent already granted, claiming, of the invention claimed in the claim of the said patent, in a valid claim of earlier priority date, contained in the complete specification of another patent granted in India. The statutory preconditions, for this clause to apply as a ground for alleging invalidation of the suit patent, are that

• the invention claimed in the claim, under consideration, of the suit patent, was claimed in another valid claim,
• said valid claim was of earlier priority date and
• said valid claim was contained in the complete specification of another patent granted in India (for ease of reference, “the prior patent”).

The court also  held that CTPR is the “invention… claimed in Claim 1 of the complete specification” in IN’307, i.e. the suit patent. The “valid claim of earlier priority date” in the prior patent, for the purposes of Section 64(1)(a), is Claim 22 of IN’978. Section 64(1)(a) would, therefore, render the suit patent vulnerable if CTPR is, prima facie, claimed in Claim 22 of IN’978. AS CTPR is not claimed, or even disclosed, in Claim 22 of IN’978. Claim 22 of IN’978 claims a Markush moiety. It is possible to travel from said Markush moiety to Claim 1 in IN’307, or to CTPR, only by cherry picking select radicals out of the innumerable choices provided in the complete specifications accompanying Claim 22 of IN’978, for substitution on said Markush moiety.

Anticipation – Section 64(1)(e)

The court held that three circumstances are, contemplated, in Section 64(1)(e) as divesting the invention in the suit patent of novelty, viz.

• public knowledge in India before the priority date of the claim in the suit patent,
•  public usage in India before the priority date of the claim in the suit patent and
• publication in India or elsewhere in any of the documents referred to in Section 13.

In order, therefore, for the defendant to be able to successfully allege that CTPR was published prior to priority date, the defendant would have to establish that CTPR was disclosed in cited patents.

However, the court held that the cited art leads the person skilled in the art to CTPR, as in the case of Claim 22 of IN’978, only when cherry picking selected substituents from the substituents suggested in the complete specifications of the cited art. The suit patent was therefore held to be prima facie novel.

The court also found the patent to be prima facie non-obvious and therefore granted an injunction against the defendants.