I have the American Express Platinum Reserve, so I'm obviously ineligible for new sign up bonuses. My wife has a supplementary card on my account. Will that still count as having an American Express issued card and thus inelgible for a bonus on a new card in her name?
It's not completely clear from where I'm standing.
From the Ts and Cs, it says: "Card members who currently hold or who have previously held any other Card product offered by American Express Australia Limited in the preceding 12 month period are ineligible for this offer."
Your wife does hold a card, but it is registered under your name...so if you want to get technical it is 'her' card but it's technically 'yours', so it could be argued either way. Best to call American Express to double check if holding a supplementary card counts.
I agree the Terms and Conditions are not clear, but in practice your wife is certainly eligible to be a 'new customer'. Supplementary cards holders do not count as customers as the card holder is liable for their spending and their credit-worthiness is not assessed, it is just an identity check.
Even better, you can refer your wife! Get her to apply through your 'refer a friend' link and you will both get points!
Get your wife to sign up for a new card, she will be classified as a new customer :) (I know from experience...)
In fact from my experience even you could sign up as a new customer and get the bonus :)