The Daily Star says City are understood to want a clause in the deal that prevents Tevez moving back to Europe in the next two years - plus a cut of any fee if he moves after that period has expired.
The FA Cup winners are also refusing to pay up the signing-on fees due on the remaining three years of Tevez's five-season contract because he asked for a move.
Corinthians and Tevez have just 24 hours to agree to the clauses before the transfer window in Brazil closes. City accept the Argentina international wants to return to South America to live with his wife and two young daughters.
But they want to guard against Tevez and agent Kia Joorabchian engineering a move back to Europe in the next two years at a higher price than they have agreed with Corinthians.