The signon bonus for the American Express Explorer card the bonus is for new card members says “Card Members who currently hold or who have previously held any Card product issued by American Express Australia Limited in the preceding 18 month period are ineligible for this offer. Previous and existing bank-issued American Express companion cardholders are eligible for this offer”
If the person who is applying holds a supplementary card on another card members’s account does that mean they wont get the signon bonus 100,000 points, or it they will get the bonus because they are not the card member?
Having a supplementary card means you qualify for the signup bonus (provided they have not hold an amex issued card as a primary card holder in the past 18 months).