Looks like I'm doing your home work

Chain linked companies
Royal Canin & the Prescription Royal Canin has two different ingredients
http://www.mars.com/global/Global+Br...oyal+canin.htm

Diamond was on Recall List
http://www.fda.gov/oc/po/firmrecalls/diamond12_05.html

Also food chain linked by Schell & Kampeter, Inc.

Canidae is their own private companies and I trust them