Microsoft allows BYOL for Amazon RDS

Microsoft now lets customers apply existing SQL Server licenses toward SQL Server usage on AWS's managed relational database service (RDS). Amazon's Bring Your Own Media (BYOM) for RDS for SQL Server covers both installation media and licensing on the managed service with no additional fees. The process requires a License Mobility Verification Form, media upload to S3, and database creation in the RDS Console. Customers can track license usage with AWS License Manager.