You should be delivering a CAD generated netlist which identifies every pad on the board (top and bottom) and it's associated net name, and xy location. In this way, if the gerber post processing does something strange, it would be caught. You have to remember that gerber artwork generation is a post process that is normally robust, but may introduce errors. If a gerber extraction is done by the bareboard mfr., number 1 - it is more expensive and 2) it will include these possible gerber errors. Most bareboard mfrs can send you the format that this netlist file should be in. Tom Kavendek Lucent Technologies Murray Hill, N.J.