No, you can't revoke their license to use the software they already have, only them breaching the license would lose them the right to use it. You could change

No, you can't revoke their license to use the software they already have, only them breaching the license would lose them the right to use it. You could change the licensing so that they are not allowed to use future versions, but then that's no longer open source software. The open source definition[0] says: "5. No Discrimination Against Persons or Groups The license must not discriminate against any person or group of persons." The last issue you get with this idea is whether the NSA is the most unethical user of these pieces of software, I seriously doubt that is the case. Then you need to introduce clauses to ban everyone else who you feel doesn't behave in the manner you'd like. That'll be fun. [0] http://opensource.org/osd-annotated http://opensource.org/osd-annotated