Amazon Elastic File System (Amazon EFS) now supports the use of setgid and sticky bit special permissions on directories. This new capability allows you to further customize access permissions for shared directories across a set of file system users. When the setgid permission is set on a directory, files created in the directory belong to the group associated with the directory (instead of the group to which the user creating the file belongs). The sticky bit is used to restrict deletion and renaming of files to the owner of the file or directory or to the root user.