There's some guys on youtube who open up C rats and similar stuff from WWII and the 'Nam era. They brought up some cans from a sunken ship, 130 years old... and while nobody ATE them, tests revealed they could still be eaten. The proteins had degraded, and much of the nutritional value lost, but no pathogens. I still have soup and chili which expired in 2009, and it's still fine. I rotate much of my nearly expiring cans to food banks though, and try and keep it somewhat current.