Use IAM to share your AWS resources with groups of AWS accounts in AWS Organizations

You can now reference Organizational Units (OUs), which are groups of AWS accounts in AWS Organizations, in AWS Identity and Access Management (IAM) policies, making it easier to define access for your IAM principals (users and roles) to the AWS resources in your organization. AWS Organizations lets you organize your accounts into OUs to align them with their business or security purpose.

Now, you can use a new condition key, aws:PrincipalOrgPaths, in your policies to allow or deny access based on a principal’s membership in an OU. This makes it easier than ever to share resources between accounts you own in your AWS environments.

For example, you might have an Amazon S3 bucket you need to share with developers and applications from accounts that are members of a specific OU. To accomplish this, you can specify the aws:PrincipalOrgPaths condition and set the value to the organizational unit ID of the caller in the resource-based policy attached to the bucket. When a principal tries to access the bucket, AWS verifies that their account’s OU matches the one specified in the policy. With this condition, permissions automatically apply when you add accounts to the OU without any additional updates to the policy.

To learn more about the new condition key, aws:PrincipalOrgPaths, you can visit the IAM Documentation.