As per the MNI: Preliminary Permit, the owner of which may request a priority right which gives exclusive exploration rights on the area. A permit may be granted for a period not exceeding 18 months. A person desiring a preliminary permit for carrying out preliminary investigations, not including test drilling, in order to ascertain the prospects for discovering petroleum, shall apply therefore to the Commissioner; the Commissioner may, in respect of such area and on such conditions as he may think fit, grant him a permit or may refuse the application