Tax-free bond specification: holders of specified NLC D-series bonds receive exemption subject to mandatory registration with issuer. Central Government specifies 10-year 9 per cent. tax-free Secured Redeemable Non-Convertible NLC Bonds (D-series) issued by Neyveli Lignite Corporation as qualifying securities for the stated exemption; the exemption is subject to the condition that the holder registers his name and holding with the issuing corporation.