–What targeting rules display an ad to users who have viewed a product, but not purchased it?–
–Positively target all product viewers AND collect purchase IDs using u-variables–
–Positively target all product viewers AND negatively target all product purchasers–
–Negatively target all product purchasers AND collect purchase IDs using u-variables–
–Positively target all product purchasers AND negatively target all product viewers–