Section 29B(3)(b) in The West Bengal Premises Tenancy Act, 1956.
(b)When acknowledgements purporting to be signed by the tenant, subtenant or their agents are received by the Controller or the registered article containing the summonses is received back with endorsements purporting to have been made by a postal employee to the effect that the tenant, sub-tenant or their agents had refused to take delivery of the registered article, the Controller may declare that there has been valid service of the summonses.