There are actually three ways a food can be labeled for nutritional adequacy. https://talkspetfood.aafco.org/readinglabels#Adequacy
The first two are the most common.
1. “___________ is formulated to meet the nutritional levels established by the AAFCO Dog (or cat) Food Nutrient Profiles for ___________.”
2. “Animal feeding tests using AAFCO procedures substantiate that ______________ provides complete and balanced nutrition for _____________.”
3. “_____________ provides complete and balanced nutrition for ___________ and is comparable to a product which has been substantiated using AAFCO feeding tests”
This is some information from AAFCO on how to read pet food labels. https://talkspetfood.aafco.org/readinglabels