STIX is released under a permissive license for any commercial or non-commercial purpose while helper scripts and related tools have individual licenses that typically follow Berkeley Software Distribution.
APT1: Exposing One of China’s Cyber Espionage Units (the “APT1 Report”) is copyright 2013 by Mandiant Corporation and can be downloaded at intelreport.mandiant.com. The STIX version was created by The MITRE Corporation with Mandiant’s permission. Mandiant is not responsible for the content of this file.
Poison Ivy: Assessing Damage and Extracting Intelligence is copyright FireEye corporation. The STIX version was created by The MITRE Corporation with permission.