Amazon S3 Object Lock support for variable retention with event holds is now available in AWS GovCloud (US-East) and AWS GovCloud (US-West). Amazon S3 Object Lock variable retention allows you to apply write-once-read-many (WORM) protection to objects whose required retention period starts with a future event, such as a contract closing or an audit completing. You place an event hold with a retention duration on an object and S3 protects the object while the hold is in place.