You can only remove customer rules from customer rule packs. You cannot modify Trellix rule packs.
To remove rules from a rule pack:
From the main menu, select Configure > Rules.
In the table of rules on the Rules page, select the Customer Rules tab.
Filter the rules list by the rule pack that contains the rule you want to remove.
Select the customer rule you would like to remove from your rule pack in the table.
On the rule detail page, click the
icon in the upper right corner of the page.In the Update Rule dialog box, select Default as the rule pack for the rule using the drop-down menu in the Rule Pack field.
Click Update Rule.
The rule is removed from your rule pack and added to the Default rule pack.