Indian patent law provides for a stricter bar and an additional test of patentability for pharmaceuticals. “Besides novelty and inventive step, pharmaceutical patents must undergo a test of Section 3(d). As per Section 3(d), mere discovery of a new form of a known substance which does not result in the enhancement of the known efficacy of that substance isn’t patentable under the Act. The explanation to the section states that substances such as salts, esters, polymorphs, etc. shall be considered as the same substance unless they differ significantly over its known efficacy,” he says. “The types of different substances enlisted in the explanation to Section 3(d) are quite large, and the lack of proper interpretation has often led to poor fate for innovations. One of the key concerns is identification of what is a known substance and known efficacy is often inconsistent and left to different interpretations by examiners. Section 3(d) is often being used and abused against the primary patents as well. It is pertinent to note that the Act nowhere bars protection of incremental innovations but only requires that it must pass the additional test of Section 3(d).”