A qualifying local authority cannot carry out an activity in respect of someone for a commercial purpose, if it is required by legislation to carry out that activity.
Ni all awdurdodau lleol cymwys gynnal gweithgaredd mewn perthynas â rhywun at ddiben masnachol, os yw'n ofynnol cynnal y gweithgaredd hwnnw o dan ddeddfwriaeth.