grep: ignore string inside parenthesis

Here is my input:

(ALL) ALL
 (root) ALL,!/bin/sh,!/bin/ksh,!/bin/csh
(ALL) NOPASSWD: ALL
(ALL) NOPASSWD: EMC_LTH
(ALL) NOPASSWD: ALL
(ALL) ALL
(ALL) NOPASSWD: ALL
(ALL) NOPASSWD: /usr/sbin/dmidecode
 NOPASSWD: ALL,!/usr/bin/rm,!/bin/rm
(ALL) NOPASSWD: /usr/bin/passwd root

I want to grep string 'ALL' so that my result is:

(ALL) ALL
 (root) ALL,!/bin/sh,!/bin/ksh,!/bin/csh
(ALL) NOPASSWD: ALL
(ALL) NOPASSWD: ALL
(ALL) ALL
(ALL) NOPASSWD: ALL
 NOPASSWD: ALL,!/usr/bin/rm,!/bin/rm