Technology for constructing a contact sharing history is disclosed. One method comprises receiving, at a computing device of a second user, a communication contact information element of a first user. The contact information is linked to a personal identification key associated with the first user. A link to a personal identification key associated with the second user is added to the communication contact information element to form the contact sharing history. The contact sharing history can then be used to identify how the second user obtained the first user's communication contact information element.