The Patents Act,1970
Section 109. Right of exclusive licensee to take proceedings against infringement
(1) The holder of an exclusive licence shall have the like right as the patentee to institute a suit in respect of any infringement of the patent committed after the date of the licence, and in awarding damages or an account of profits or granting any other relief in any such suit the court shall take into consideration any loss suffered or likely to be suffered by the exclusive licensee as such or, as the case may be, the profits earned by means of the infringement so far as it constitutes an infringement of the rights of the exclusive licensee as such.
(2) In any suit for infringement of a patent by the holder of an exclusive licence under sub-section (1), the patentee shall, unless he has joined as a plaintiff in the suit, be added as a defendant, but a patentee so added as defendant shall not be liable for any costs unless he enters an appearance and takes part in the proceedings.