Omitting the AS grantor Clause

When GRANT FRAGMENT does not include the AS grantor clause, the user who issues the statement is the default grantor of the specified fragment privileges.

In the next example, the user grants the Update privilege on the fragment of the customer table in part3 to user fred. Because this statement does not specify the AS grantor clause, the user who issues the statement is listed by default as the grantor of the privilege in the sysfragauth system catalog table. 
GRANT FRAGMENT UPDATE ON customer (part3) TO fred;

If you omit the AS grantor clause of GRANT FRAGMENT, or if you specify your own login name as the grantor, you can later use the REVOKE FRAGMENT statement to revoke the privilege that you granted to the specified user. For example, if you grant the Delete privilege on the fragment of the customer table in part3 to user martha but specify user jack as the grantor of the privilege, user jack can revoke that privilege from user martha, but you cannot revoke that privilege from user martha.

The DBA, or the owner of the fragment, can use the AS clause of the REVOKE FRAGMENT statement to revoke privileges on the fragment.