Selection Patents in India

April 19, 2022

By Ranu Bala Rampal and Johny Solomon Raj

What is Selection Patent?

Selection patent refers to the inventions that are individually novel but selected from a collection of already existing inventions. Such inventions exhibit special advantage over the already existing inventions.[1]


Selection patent can also be defined as the inventions that claim a specific compound to be separately novel but falling under previously known large group of substances for which the protection has already been claimed.[2]


Selection inventions involve selecting subsets, individual elements and sub-ranges that have not been particularly disclosed previously, within a broader known range/set. [3]


Selection patents are mostly obtained for chemical compounds and pharmaceutical inventions. However, it is not just limited to inventions related to life sciences but also applicable in the field of biotechnology, engineering, telecommunications and material science. The selection patents are also preferable for invention involving a manufacturing processes. For instance, in an already disclosed process where operating conditions such as pressure and temperature within a specific known range results in unpredictable effects or improved properties of the formed products, the selection patent is favoured.

Selection Patent under the Indian Patent Law

  • Criteria for Patentability of Selection Patent
  1. There is no special provision for selection patents in the Indian Patents Act. The selection patents are similar to other patent applications However, for an invention to be capable of selection patent, it must possess three main criteria of patentability including novelty, inventive step and industrial applicability as per section 2(1) (j) of Indian Patents Act. Furthermore, the invention should not fall under section 3 and section 4 of the Indian Patents Act.


  1. In order to overcome objections as per section 3(d), it is important for selection patents to exhibit a new form of already known substance leading to enhancement in efficacy of the known substance.[4]
  2. For an invention to be capable of selection patent, a particular group of compounds disclosed in the invention selected from previously existing broad group of compounds should exhibit advantages which are not shown by previously existing group of compounds.

Concept of Novelty with respect to Selection Patent

  • Inventions where with the selection of one or more specific embodiments from a general disclosure in the prior art, a new invention is carved out are known as selection inventions.
  • The Indian Patent Office has no specific guidelines for evaluating the novelty with regard to selection invention unlike other jurisdictions.
  • Generally, a disclosure in already known invention is not regarded as a threat for any other invention claiming a specific embodiment of the previously known invention. For instance, if an already existing invention relates to a metal, other invention claiming a particular metal such as calcium would still be regarded as a novel. Moreover, selection of particular dimensions or a range of various parameters, within a previously known broader values depending on new features, unexpected results and new characteristics, are capable of selection patent as per section 2(1)(J). However, the criteria for novelty in case of selection patents may become complex in case of prior known inventions relating to ranges, lists and so on. The Indian Patent Law relating to novelty of selection patents including ranges/lists has not much emerged as compared to other jurisdiction.

Concept of Inventive Step with respect to Selection Patents

Indian courts practice rules put forward by UK decision in Interessengemeinschaft Farbenindustrie AG Patent for assessing the presence of an inventive step in selection invention. The UK decision put forward four major conditions for an invention to be capable of selective patent:

  1. The selection depends on some significant advantages attained by using selected members of a previously patented substance
  2. All the selected members should exhibit advantages
  3. The selection is based on the quality of the unique traits that are distinctive to the selected group
  4. The features/traits exhibited by the selection that a patentee wishes to claim, shall be clearly defined. [5]

The Viewpoint of Indian Patent Office

  • Although no specific provision exist regarding the selection patent, the Indian Patent Office do not entirely deny the patentability of the selection patents.


  • Keeping in view the importance of novelty as an essential criteria for assessing selection invention, the Indian Patent Office has mentioned in its manual (The Manual of Patent Office Practice and Procedure) “a generic disclosure in the prior art may not necessarily take away the novelty of a specific disclosure. However, the manual also mentions that “A specific disclosure in the prior art takes away the novelty of a generic disclosure.  Thus, the Manual of the Indian Patent Office submits that the Indian Patent Office will not unquestionably deny the selection patents in terms of novelty rather it shall closely assess specific and generic disclosures alongwith analysing validity thereof.


  • Also, the guidelines on patentability of pharmaceutical related inventions discloses that such inventions may include claims relating to selection invention such as process or product. Further, the guidelines also states that a generic disclosure shall not take away the novelty of a specific disclosure.


  • The guidelines provides various examples with regard to selection patents. One such example includes – an invention including the claimed compounds of markush claims falling under the markush claims of already existing inventions. In such case, the guideline provided by the Indian Patent Office states that it is necessary to check if the compounds disclosed in already existing inventions are of a structure such that they can clearly take away the novelty of compounds under consideration. If the compounds of existing invention disclosed do not take away novelty of the compound under consideration then the generic disclosure in the existing invention may be cited to prove the inventive step.


  • Another example includes fumaric acid salt of a compound implicitly disclosed when the already existing invention enables just methane sulfonic acid salt however discloses fumaric acid amongst an exhaustive list of salt forming acids.


  • With regard to the implicit disclosure, the guidelines further includes that absence of novelty must normally be obvious from explicit teaching of previously existing invention. In case the disclosure in previously existing invention is too implicit that it leaves no confusion in the mind of the controller then objection relating to novelty should be put forward. Further, it states:


  • The lack of novelty must normally be clearly apparent from the explicit teaching of the prior art. However, since the prior art is read through the eyes of the person skilled in the art, the implicit features of a document may also be taken into account for determining novelty. Thus, if the person skilled in the art would read a disclosure as including a particular feature without it being specifically mentioned, it would be considered an implicit feature of that disclosure and lack of novelty may be implicit in the sense that, in carrying out the teaching of the prior document, the skilled person would inevitably arrive at a result falling within the terms of the claim.”1


  • However, the guidelines provide that a generic disclosure do not particularly take novelty of a specific disclosure but simultaneously it also provides that the absence of novelty should not be implicit in the previously existing inventions.


  • Below mentioned are some of the decisions of the controller regarding inventions including selection from previously existing inventons.


  1. 1879/KOLNP/2009 (Status- Granted): The controller granted the application since the claimed compounds of the invention exhibits enhanced activity as compared to the compounds disclosed in previously known invention.


  1. 2784/CHENP/2007 (Status-Rejected): The controller rejected the application since no enhanced activity of the compound was identified.


  1. 2196/DELNP/2003 (Status- Granted): The controller granted the application based on the status of selection patents in India. The controller stated “The arguments regarding the selection patent is acceptable and the present invention very well comes under category of the selection patent and fulfills all the norms as per the well established practice in India for grant of a selection patent.”1


  • The earliest jurisprudence with regard to selection inventions dates back to 1969 in one of the most popular Unichem Laboratories’ case. The Bombay High Court made the following statement:


“Even where an invention consists of the production of further members of a known series whose useful attributes have already been described or predicted, it may possess sufficient subject matter to support a valid patent provided the somewhat stringent conditions prescribed by Maugham. J., as he then was, in I.G. Farbenindustrie A.G.’s Patents (1930) 47 RPC 289 as essential to the validity of a selection patent are satisfied, i.e. the patent must be based on some substantial advance to be gained from the use of the selected members of the known series or family of substances, the whole (or substantially the whole) of the selected members must possess this advantage, and this advantage must be peculiar (or substantially peculiar) to the selected group.”1


Thus, the concept of ‘selection patent’ was not identified by the Bombay High Court. However, the court mentioned that the selected members should exhibit an advantage significant to the selection.


  • In another decision of the Single Judge dated November 18, 2020, the following statement was made regarding selection patents:


Although selection patent was covered under Markush formula but not explicitly and clearly disclosed in the Markush formula could be successfully granted a patent. However, the selection patent must exhibit significant advantage or avoid disadvantage as compared to the previously existing inventions by utilizing selected members of the existing inventions. Thus, the decision do not entirely prohibit the likelihood of the grant of selection patent. Also, the division bench considered if patent application IN 625 possesses any technical advancement over the patent application IN 147. Therefore, it may be concluded that if selection invention exhibits technical advancement over the previously existing invention then selection patent could be granted patent. 1


  • In 2009, Indian Patent Appellate Board, in one of the popular case of Novartis Imatinib, put forward that no specific provision exist with respect to selection patent. However, if the main criteria of patentability that is novelty, inventive step and, industrial applicability alongwith patentability disclosed in section 3 and section 4 of Indian Patent Act are fulfilled, then the inventive step can indicated by inventive selection. Further, IPAB stated that “In the context of a selection patent the inventive step will generally lie in making the discovery that what has been selected provides a genuine advantage over the generality from which it was selected. The advantage being one that could not be predicted.” [6]


  • Further, the Indian Patent Appellate Board put forward various guidelines in respect of patentability of selection inventions in the same case. The conditions illustrated by the guidelines are as follows:


  1. If specification includes any statement disclosing the nature of the invention relates to selection of some kind.
  2. If the selection occurs from a previously known class of substance.
  3. If the substance selected is novel.
  4. If the selection results from research by human interference and inventiveness opposed to mere affirmation.
  5. If the selection is unpredictable or unexpected.
  6. If the substance selected exhibits any kind of advanced and unexpected property.


Thus, as per Indian Patent Appellate Board, an inventive selection of advanced, unexpected, and new single member from an already known series of a genus can be accepted but the main element of the selection invention should be in the main specification only. 5


  • Evergreening is an important aspect in patenting of a pharmaceutical invention. The patent holders wish to increase the patent term by filing an invention based on already existing patent applications. Section 3(d) of Indian Patents Act prevents the concept of Evergreening by inhibiting the patenting of new forms of an already known substance unless the new form exhibits enhancement in efficacy as compared to that of an already known substance. As per section 3(d), the new forms may include esters, ethers, salts, polymorphs, etc.


  • The concept of Evergreening becomes more significant when the same applicant as that of the existing invention files the selection patent.


  • The Supreme Court of India passed a landmark judgement on the evaluation of Section 3(d) in one of the popular Novartis’ Imatinib case (2013). With regard to selection patent, one major argument taken by Appellant include that there exist difference between what is covered and what is disclosed. However, according to the Supreme Court, coverage should be regarded equivalent to the disclosure. The Supreme Court made the following statement in its judgement: [7]


We certainly do not wish the law of patent in this country to develop on lines where there may be a vast gap between the coverage and the disclosure under the patent; where the scope of the patent is determined not on the intrinsic worth of the invention but by the artful drafting of its claims by skillful lawyers, and where patents are traded as a commodity not for production and marketing of the patented products but to search for someone who may be sued for infringement of the patent.”[8]


Therefore, the Supreme Court was not much in favour of accepting the differences between coverage and disclosure. The Supreme Court discovered that the part covered by the embodiments of specification shall be regarded as disclosed therein. .


  • Further, as discussed, apart from three basic criteria of patentability, it is required that in the selection invention, the claimed modifications should exhibit enhanced efficacy as compared to that of an already existing substance. Further, the term efficacy in case of drugs relates to therapeutic efficacy. Therefore, an invention is required to fulfil the conditions as per section 2(1) (j) and section 3(d).


  • Furthermore, with regard to selection patents in India, two more concepts play an important role especially in regard to therapeutic moieties:
  1. The novelty of the selected members has to be explained on the ‘disclosure vs coverage’.
  2. As and when the selected member is regarded to be novel (in absence of an ‘enabling disclosure’), the patentability as per section 3(d) must be established, as the selected member can then also be considered as a new form of structurally closest already existing members. 1
  • The inventive step of the selected members may be illustrated by improvement in physio-chemical properties however in order to avoid objection of section 3(d), it is required to exhibit enhanced efficacy i.e. the therapeutic efficacy of drugs/medicine/chemicals of the selected member over the previously existing patent applications.

Aastha Suri, Patent Agent at S.S. Rana & Co. has assisted in the research of this article.










For more information please contact us at :