Abstract: An asset server receives electronic asset data from electronic asset data sources. The electronic asset server receives a request to provide a client with an electronic asset. Based on the request, and optionally using a bidding system, the electronic asset server selects a particular asset described by the electronic asset data, from a particular asset data source, to provide to the client. The electronic asset server stores a delivery record in a repository of delivery records, indicating the sending of data for the particular asset to the client. The electronic asset server receives an event message from the client describing an event that occurred at the client with respect to the particular asset. A correlation component correlates the event message to the corresponding delivery record, if possible. Based on the correlation, a notification component sends a notification message indicating the occurrence of the event to the particular asset data source.