Express scripts fills generic prescriptions from Manufacturers (mostly from India and China) who received violations warning letters from the FDA. The one company they used to fill my generic Lipitor RX is Apotex.
Research it and you'll see Apotex Group's Indian manufacturing company, Apotex Research, picked up a warning letter from the Food and Drug Administration following an inspection last November that revealed a number of significant violations of current good manufacturing practices (cGMP). The company has been on import alert since April 2018. Always check to see who manufacturers you medicine.