The court also confirmed the Central Bureau of Investigation (CBI) Special Court 2010 ruling of two-year jail for three others in the case.
In 1994, Mr Natarajan imported a new Lexus car forging the papers to show that it made in 1993 and thus evaded a duty of over Rs 1.6 crore.
The CBI had registered a case against Natarajan, his nephew V Baskaran, Balakrishnan, his son Yogesh Balakrishnan and two officials of the Indian Bank, of which one turned approver.
Income Tax officials recently searched the premises of Mr Natarajan for tax evasion.
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