Facts

Amincor Bank AG opened a current account for Hector Lopez Fontana. On November 14, 1972, a payment order from Chemical Bank New York in favor of Hector Lopez Fontana in the amount of US$7,500.-- was received at the Chiasso branch. The Chiasso branch paid Hector Lopez Fontana the equivalent of the ordered dollar amount, which was CHF 28,458.70, on the same day. It later turned out that the transfer from the National Bank had been made on the basis of a forged order.

In the meantime, the National Bank had obtained an attachment order against Hector Lopez Fontana for a claim of approximately CHF 45,000.-- due to the fraudulently initiated transfer. The Debt Collection Office Zurich 2 informed Amincor Bank that all credits and assets of the debtor subject to the attachment, including the current account balance, were seized for the attachment claim.

Amincor Bank informed the Debt Collection Office that the balance of the debtor's credit as of January 10, 1973 was CHF 385.-- and US$9,494.65. After Amincor Bank discovered that it had not taken into account the reversal of the credit in connection with the payment order from Chemical Bank when calculating the balance reported to the Debt Collection Office and already paid out, it claimed the amount of US$7,500.-- or CHF 28,575.-- by way of set-off.

Considerations

The Federal Court decided that the setting off of the current account balance against the Debt Collection Office did not constitute a novation within the meaning of Art. 117 para. 2 CO. Such a novation could only have occurred through the recognition of the balance by the plaintiff's contractual partner, i.e., the debtor subject to the attachment, Fontana.

If a claim is attached or garnished, the defenses available to the claim remain with the debtor. This includes in particular the defense of set-off. It is not necessary for the set-off to have been permissible and declared at the time the third-party debtor became aware of the attachment. It is sufficient if the debtor had the prospect of being able to set off at that time.

The credit in favor of the debtor subject to the attachment, which the plaintiff made on the basis of the…