When searching bidders, a way to search FOR say, Roofers (CSI7500 / NIGP-91473), but EXCEPT for those that also do "Construction Management" (CSI-01000 Gen. Cond. Misc Trades / NIGP-91268).

Basically a way to exclude other General Contractors, that have listed themselves as performing various trade work (though they sub it out), so that we only notify the "true" roofing subs.