Section 39(1) in The Bihar Industrial Disputes Rules, 1961
(1)Where there are numerous workmen affected by a notice of change and the majority of such workmen are members of any trade Union, the service of notice, by registered post on the Secretary, or where there is no Secretary, on the Principal Officer of the Trade Union shall be deemed to be service on all such workmen. The employer shall, at the same time, arrange to exhibit the notice by affixing it to a notice board in the manner specified in sub-rule (2):Provided that if the Secretary or the Principal Officer refuses to receive the notice or that for any other reason the notice cannot be served on the Secretary or the Principal Officer in the manner prescribed in sub-rule (1), the exhibition of the notice in the manner specified in sub-rule (2) shall be deemed to be service on all such workmen.
