In one embodiment, a method includes receiving usage data regarding usage of a subscription-based media service account, generating a plurality of sharing scores based on the usage data, each of the plurality of sharing scores being indicative of a confidence that the usage of the subscription-based media service account is subject to a respective type of sharing, comparing each of the plurality of sharing scores to a respective threshold, and, in response to one of the plurality of sharing scores exceeding its respective threshold, presenting a challenge associated with the respective type of sharing.