Three ox drivers from Adab were thirsty: one owned the ox, the other owned the cow and the other owned the wagon’s load.
The owner of the ox refused to get water because he feared his ox would be eaten by a lion;
the owner of the cow refused because he thought his cow might wander off into the desert;
the owner of the wagon refused because he feared his load would be stolen.
So they all went.
In their absence the ox made love to the cow which gave birth to a calf which ate the wagon’s load.
Problem: Who owns the calf?
Abbreviated rendition via Reema’s My Random Thoughts, who places it at 1200 BCE (though that would definitely be post-Sumerian).
The original has several lines missing, so we don’t really know the Sumerians’ answer to this. Good thing you’re not being tested.