Amazon AppStream 2.0 is now in scope under AWS’s latest System and Organizational Controls (SOC) audit cycle. This SOC compliance certification applies to all AWS Regions where Amazon AppStream 2.0 is available.  

from Recent Announcements: https://aws.amazon.com/about-aws/whats-new/2019/12/amazon-appstream-2-is-in-scope-for-aws-latest-system-and-organizational-controls-audit-cycle/