Section 2(6)(b) in The Merchant Shipping (Prevention of Pollution by Oil from Ships) Rules, 2010
(b)an agreement has been entered between the Central Government and the Government of the Port States referred to in clause (a) and (b) of sub-rule (5) concerning the use of an oil tanker delivered on or before the 1st June, 1982, as defined in clause (33) of rule lA, for a specific trade;