Honestly I do not believe that there is a "official" certification authority for DEF. Even API certification is voluntary. The key is that the DEF meets ISO22241 standards, which is what API will be using for its certification standards/minimums. The API certification will just give consumers proof that the DEF indeed meets the ISO standards and by doing so should eliminate any issues with Ford.

Here is a link to the API DEF site... Welcome to the API Diesel Exhaust Fluid Certification Website!