Since pennies are not legal tender, he can legally keep the pennies and sue for the $900.
Sigh.
Pennies are legal tender.
“United States coins and currency (including Federal reserve notes and circulating notes of Federal reserve banks and national banks) are legal tender for all debts, public charges, taxes, and dues. Foreign gold or silver coins are not legal tender for debts.”
Just because they are legal tender, doesn’t mean that businesses have to accept them.
“[A]ll United States money … is a valid and legal offer of payment for debts when tendered to a creditor. There is, however, no Federal law mandating that a person or organization must accept currency or coins as for payment for goods and/or services.”