We emailed Publix for their coupon policy. They did not send a complete coupon policy, but instead provided a few notes. Since coupon policies can change frequently, take this as a starting point, and confirm details with your store.
Publix Coupon Notes:
We don't have a documented coupon policy, as our goal is simply to accept coupons and adhere to the stipulations printed on the coupons. You'll be happy to know that we do accept a manufacturer's coupon and a Publix store coupon on the same item unless the coupon specifies differently. All stores should be accepting coupons based on the stipulations printed on the coupons.
The only area where stores may differ is in regards to competitor coupons. Typically, we consider traditional super markets as competitors, but not warehouse clubs or pharmacies. Since we operate in five states and the competitors vary from area to area, our store managers determine who the competitors are in their areas. I would suggest checking with the store manager where you will be shopping if you have questions about a particular competitor.