Patent ID: 7801960

Claim:
A method for monitoring electronic mail messages comprising: receiving at a computer an electronic mail message comprising message content and header information, wherein said header information consists of subject header information and non-subject header information; generating a message digest from only the subject header information and the message content of the e-mail message; using an algorithm executed by the computer to generate a characteristic numerical representation of at least a part of said message digest, wherein the message digest is generated using a message digest algorithm, and wherein the message digest algorithm is a hash algorithm; storing said generated characteristic numerical representation in a memory of the computer; comparing said characteristic numerical representation with each characteristic numerical representation stored in the memory; if said characteristic numerical representation matches a previously-stored characteristic numerical representation, incrementing a count value associated with said characteristic numerical representation; determining that said received electronic mail message is an unwanted message if the incremented count value associated with said characteristic numerical representation matches a predetermined number; and determining an originator of said received electronic mail message if it is determined that said received electronic mail message is an unwanted message.