199.15.0.0 - 199.15.7.0 Illinois Secretary of State (NETBLK-TBLK-ILLSOS) 199.15.8.0 - 199.15.15.0 Metropolitan Sewer District (NETBLK-TBLK-MSD-NET) 199.15.16.0 - 199.15.25.0 Burle Industries, Inc. (NETBLK-BLK-BURLE3 ) 199.15.32.0 - 199.15.63.0 National City Processing Company (NETBLK-TBLK-NATLCTYPRCCO) 199.15.64.0 - 199.15.73.0 Metropolitan Sewer District (NETBLK-TBLK-MSD-NET2)