Section 49(4)(a) in West Bengal Trade Unions Rules, 1998
(a)At time of issuing a ballot paper to a voter, the Polling Officer shall(i)record on its counterfoil electoral roll number of the voter as entered in the marked copy of the electoral roll ; and(ii)mark the name of the voter in the marked copy of the electoral roll to indicate that a ballot paper has been issued to him, without however, recording therein the serial number of the ballot paper issued to the voter.