This ground applies where a supplier has acted improperly in a procurement and, as a result, has put itself at an unfair advantage in relation to the award of a public contract.
Mae'r rheswm hwn yn berthnasol os yw cyflenwr wedi gweithredu'n amhriodol mewn proses gaffael ac, o ganlyniad, mae ganddo fantais annheg mewn perthynas â dyfarnu contract cyhoeddus.