In other cases, however, we know the relief was claimed but other aspects of the transaction were incorrect, which led to the assumption that the relief had no effect.
Mewn achosion eraill, fodd bynnag, rydym yn gwybod bod y rhyddhad wedi'i hawlio ond bod agweddau eraill ar y trafodiad yn anghywir, a arweiniodd at y dybiaeth na chafodd y rhyddhad unrhyw effaith.