Patents Act, 1970
19. Powers of Controller in case of potential infringement
(1) If, in consequence of the investigation required by the foregoing provisions of this Act or of proceedings under section 25, it appears to the Controller that an invention in respect of which an application for a patent has been made cannot be performed without substantial risk of infringement of a claim of any other patent, he may direct that a reference to that other patent shall be inserted in the applicant's complete specification by way of notice to the public, unless within such time as may be prescribed-
(a) the applicant shows to the satisfaction of the Controller that there are reasonable grounds for contesting the validity of the said claim of the other patent; or
(b) the complete specification is amended to the satisfaction of the Controller.
(2) Where, after a reference to another patent has been inserted in a complete specification in pursuance of a direction under sub-section (1)-
(a) that other patent is revoked or otherwise ceases to be in force; or
(b) the specification of that other patent is amended by the deletion of the relevant claim; or
(c) it is found, in proceedings before the court of the Controller, that the relevant claim of that other patent is invalid or is not infringed by any working of the applicant's invention.
the Controller may, on the application of the applicant, delete the reference to that other patent.