Patent ID: 8316094

Claim:
A computer-implemented method for identifying spam mailing lists, at least a portion of the method being performed by a computing device comprising at least one processor, the method comprising: identifying a plurality of clients that receive e-mail messages; for each client in the plurality of clients: receiving, from the client, information identifying at least one e-mail message received by the client; recording the identifying information in a database; using the identifying information from the database to infer existence and targets of a spam mailing list, the targets of the spam mailing list being inferred by identifying at least one group of clients within the plurality of clients with similar patterns of identifying information; wherein identifying the group of clients with similar patterns of identifying information comprises performing a statistical analysis on the identifying information stored in the database to infer existence of the spam mailing list; determining that a first client in the group of clients received a new spam e-mail message; and using the spam mailing list to distribute a signature of the spam e-mail message to each client in the group of clients other than the first client.