Restrict access to all resources within an AWS account to only principals from the organization

aws-scp-restrict-org.json

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "RestrictAccessToOrg",
            "Effect": "Deny",
            "Action": "*",
            "Resource": "*",
            "Condition": {
                "StringNotEquals": {
                    "aws:PrincipalOrgID": "o-1234567890"
                }
            }
        }
    ]
}