University of New Mexico student Jeffrey Knockel claims to have revealed an encrypted list of 1,100+ keywords within China's Skype client, TOM-Skype. This list, containing words like "BBC" and phrases like "Democratic Unionist Party", are suspected to be used for monitoring TOM-Skype users.

When a TOM-Skype user sends chat messages containing "suspicious" language found within the program's periodically updated keyword list, Knockel's research indicates an alert is sent to TOM-Skype's servers containing the sender's account name, message timestamp and detected word(s). The list was uncovered after Knockel had been monitoring suspicious communications between TOM-Skype and its Chinese servers. The collection of words was encrypted, but Knockel was able to employ some clever analytical techniques and reverse-engineering, which eventually lead to its uncovering.