Patent ID: 8874672

Claim:
A method comprising: maintaining, in a storage device, a list of people who are known to a user; detecting one or more actions performed by the user on one or more messages received by the user from a person, the actions including one or more of (a) saving the one or more messages from the person; (b) printing the one or more messages from the person; (c) moving the one or more messages from the person from an inbox to a folder; (d) leaving the one or more messages from the person open for a predetermined period of time; and (e) replying to the one or more messages from the person; determining, using at least one processor, that the person is known to the user based on a score associated with the detected one or more actions, wherein the score is determined from two or more associated scores, and wherein the score supports a positive inference that the person is known to the user; in response to determining that the person is known to the user, updating the list of people to reflect that the person is known by the user; and communicating, to the user via a messaging application, presence information based on the updated list of people known to the user.