New Forms of a Known Substance

1The first part of s 3(d) contains a conditional exception to patentability. It pertains to a product patent. The first part reads as follows:

3. What are not inventions. – The following are not inventions within the meaning of this Act, –

… (d) the mere discovery of a new form of a known substance which does not result in the enhancement of the known efficacy of that substance…

2The effect of the first part is that it allows for the discovery of a new form of a known substance to be treated as an invention if there is an enhancement of its known efficacy. It is the discovery which leads to the claiming of the particular result in the form of a patentable invention. The first part of s 3(d) states that such mere discoveries cannot amount to an invention under the Patents Act. It follows that the properties pursuant to such discovery, which are devoid of any inventive step, will not be allowed to be the subject matter of a patent.

3If the Patents Act were to allow for a new form of a known substance without the conditional clause on efficacy, it would mean that the novelty of the invention will lie in its form. Such a provision can have an uncertain effect in the case of chemicals and pharmaceuticals, a field in which obtaining new forms of a substance is possible and sometimes can be achieved with consummate ease. Thus, the requirement of the invention to have novelty of effect, ie, increase in known efficacy, may be viewed as a reasonable requirement.

4The full impact of the first part of s 3(d) cannot be understood without considering the second part of s 3(d). This is because while the first part requires a new form of a known substance to differ significantly in 'properties' with regard to efficacy, the second part comprehensively bans any new 'property' of a known substance. It might appear that the second part of s 3(d) subsumes the first part of s 3(d), as both deal with properties of known substances. This might raise an issue whether, in such a case, the effect of the first part is nugatory. That is not so. A careful reading of the first part will reveal that new form of a known substance will qualify for an invention if there is an enhancement of a 'known property', ie, efficacy of the substance. As the first part pertains only to an increase or enhancement of a 'known property', it is submitted that the first part will not be affected by the second part which bans a 'new property'. But if the enhancement of a known property is to be regarded as a new property, then the second part may be applicable.

5The Patents Act provides for patents for improvements. Whether a particular invention will qualify for an improvement will depend on facts and circumstances of each case having regard to the technical advancement over the earlier invention. (Patents Act 1970, s 2(1)(ja).) Similarly, 'enhancement of the known efficacy' should also be determined having regard to the known efficacy and the significant difference made through the enhancement. A new product or a process could also mean a new improvement over an existing product or a process. Every improvement cannot qualify for a patent, but improvements on the prior art so long as it satisfies the prerequisites of patentability, can qualify as a patentable invention. Mere workshop (laboratory) improvements, devoid of ingenuity, will not qualify for a patent. (Bishwanath Prasad Radhey Shyam v Hindustan Metal Industries AIR 1982 SC 1444, p 1453; Polar Industries Ltd v Jay Engineering Works Ltd 1989 PTC (Supp) (2) 310 (Cal).)

6The requirement of 'enhancement of the known efficacy' is not a requirement unknown to law. In plain terms, 'enhancement of the known efficacy' means an improvement on what is already known. (See Novartis Application 1602/MAS/98 (Unreported) where the Controller equates 'enhancement' with 'improvement'.) It is a well-established principle in patent law that improvements are patentable. To qualify for a patent, an improvement must by itself satisfy the test of patentability. An improvement or modification of an earlier patent may qualify for a patent as a patent of addition. (Patents Act 1970, ss 54-56.)

7The explanation to s 3(d) creates a rebuttable presumption that salts, esters, ethers, polymorphs, metabolites, pure form, particle size, isomers, mixtures of isomers, complexes, combinations and other derivatives of known substance shall be regarded as the same known substance. It will be for the applicant to rebut this presumption by showing that the new form of the known substance 'differs significantly in properties with regard to efficacy'.

8The provision protects incremental innovation. In Cipla v F Hoffmann-La Roche (2015) (paras 62, 73 and 85) the Division Bench held that section 3(d) "is not a patent term extension or an evergreening provision but in fact recognizes incremental innovations in pharmaceutical patents." The Court further observed that the provision cannot be interpreted as a defence to infringement. Polymorphs, which are regarded as new forms of known substances under this provision, that improve only non-therapeutic properties will not be eligible for grant of a patent.