Hello, XXXXXXX,
You pose an interesting practical question.
If you look at any good brand soup can,
there is a date that says "Best if used by this date"
whatever that date or year might be. That refers
to the best quality taste of the soup. There is no
expiration date as such. But the recommendation
from communicable centers for diseases would be,
if the can is dented or damaged or looks bulging
don't use it. Obviously after pouring the soup from
the can, if it smells or looks fermented or discolored
don't use it.
I guess people had canned food found in the bomb
shelters in the 60s and 70s. that was still good.
Use your judgement and commonsense.
Good luck and stay healthy.

---