In India, not everything under the Sun is patentable in contrary to US Patent system. In order to remove ambiguity, the inventions, which are not patentable even though they fulfil the patentability criteria [Novel, Inventive and Industrial Applicable], are clearly specified in the Patent Act (Chapter II which includes Sections 3, 4 and 5). Some inventions are excluded, as they do not have a technical effect while others are excluded on moral grounds. Also, inventions, which relate to atomic energy, are strictly not patentable (Section 4).
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