Section 159(6) in The West Bengal Motor Vehicles Rules, 1989
(6)Upon receipt of Parts A and B of the permit and of the prescribed fee, [as specified in Schedule A,] [Inserted vide clause 2(12) of the Notification No. 5305-WT/6M-21/2002 dated 12.12.2003 (w.e.f. 16.12.2003).] the Regional Transport Authority or state Transport Authority, shall cancel the particulars of the holder thereon and endorse particulars of the transferee and shall return the permit to the transferee.