A server device is configured to receive a comment associated with a first document, the comment corresponding to a first portion of the first document; identify a second document that includes a second portion that matches the first portion of the first document; and store the comment in association with the first document and the second document. The server device is further configured to receive, from a client device, information that the client device is accessing the second document, and transmit the comment for presentation in connection with the second document on a display associated with the client device.