NetApp
Configuration > System Tools > Licenses : Managing licenses : Deleting a license
Deleting a license
You can delete a software license from the Licenses window.
About this task 
Your storage system requires certain software licenses to enable some services and features. Before deleting a software license, you must check the list of required licenses in License Requirements.
Steps 
1.
From the Home tab, double-click the appropriate storage system.
2.
In the navigation pane, click Configuration > System Tools > Licenses to display the Licenses window.
3.
Select the software license you want to delete, then click Delete.
4.
Select the confirmation check box and click Delete.