I just noticed this today. Wells Fargo has over $1 trillion in short-term (less than 1 year) liabilities, for which it pays 0% interest. When the debts mature, they are just rolled over.
No one else seems to have noticed this phenomenon or cares about it. Obviously it is a government agency, because anyone else could get at least a minimal amount of interest. If I can find out anything else about it I will post it.
Update: I can't find anything else about this. It appears to be a mistake.