Dann v. Johnston, 425 U.S. 219, 189 U.S.P.Q. (BNA) 257 (1976) (full-text).
Factual Background Edit
A patent was sought for a computer system for automatic record keeping of bank checks and deposits. By using machine readable checks and deposit slips bearing numerical category codes for various types of expenditures and sources of deposited funds, the system permitted a bank to furnish a customer with subtotals for each category of transactions conducted through the customer's single bank account.
U.S. Supreme Court Proceedings Edit
The Court ruled that the computer system was not patentable on the ground of obviousness. A patent may not be obtained if the subject matter would have been obvious at the time the invention was made to a person having ordinary skill in the art. The relevant prior art was held to be that of computer technology rather than the art of the banking industry.