patent legislation in the world, and was intended as a response to concerns over patents that extend the total duration of protection for a drug beyond the protection offered by the basic patent claiming the active ingredient.<sup>12</sup> Despite its official patent standards, the Indian Patent Office is in fact granting numerous product patents on incremental innovation that do not meet the efficacy requirement.<sup>13</sup> In recent work, Sampat (2010) argues based on aggregate data on pharmaceutical patent applications and grants in India, that section 3(d) requirements of India’s patent law, which limits patents on incremental pharmaceutical innovations, is often ignored, and the standards of patentability, however high, are not implemented in practice.

It is worth noting that some patents are more likely to exclude generic entry than others. As described by Hemphill and Sampat (2010), a product patent claiming the active ingredient – basic patents that cover the drug compound are generally the strongest and will most likely prevent any use of the same drug. In comparison to patents on active ingredient, patents for a particular formulation (or chemical variants) such as a sustained release version of the drug may not exclude generic entry since a local manufacturer may be able to employ a different, non-infringing mechanism for accomplishing the sustained release of the drug.

Some of the other major flexibilities under TRIPS that are available in the Indian patent law are provisions relating to Bolar Exemption<sup>14</sup> and parallel imports<sup>15</sup> . Compulsory licensing and government use authorizations are also options that are permitted under 12 Developed countries, for example USA, follow very liberal patent standards. Patents are granted not only for new chemical entities (NCEs) involved in the new drugs but secondary patents can also be taken for new formulations, new combinations and new uses of existing NCEs even if these new products provide no clinical benefits (Chaudhuri 2005). Moreover since the secondary patents can be taken later and would be valid even after the expiry of the patents on NCEs, this could extend the patent life beyond 20 years thereby delaying the entry of generics.

13The section 3(d) provision has been the most controversial clause of the Indian Patent Act of 2005 and litigation has already ensued over this provision. India's new patent regime provides for both ex ante and ex post opposition procedures that could be based on any patentability criteria that can be challenged, including the lack of novelty, inventive step, utility, non-eligible subject matter, the failure to disclose the source of biological material used for the invention, and inventions which are considered traditional knowledge. On the one hand, this procedure is likely to lengthen the patent prosecution process and make the outcome more unpredictable. On the other hand, Indian generic pharmaceutical manufacturers favored retention of litigation mechanisms in the new Patents Act to prevent ever greening, and thus far generics have strategically used the procedure frequently. Decisions on recent pharmaceutical pre and post grant opposition cases can be found at http://www.i-mak.org/pharma-patent-decisions/.

14 Under section 107A(a) of the 2005 Patents Act, use of a patent for development and submission of information for regulatory approval will not be considered as an infringement of the patent right. Thus in the new patent regime, as innovator companies introduce new drugs in India and enjoy exclusive patent rights, such Bolar provisions can be used to introduce generics immediately after the expiry of patents. 15 Under section 107A(b) 2005 Patents Act, importation of patented products by any person from a person who is duly authorized by the patentee to sell or distribute the product, shall not be considered as an infringement of patent rights. This clause effectively permits parallel imports.

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