The feature would revert to default, or "as-is" when not licensed - and stop working.
Each of the software components, or features, of the Content Security appliance is licensed and must be enabled before use. In order to enable these components, you must apply keys that are provided by Cisco. Each key is specific to the serial number of the individual Content Security appliance and has an expiration period that is associated with it. When a key expires, you must renew the contract for that feature with your Cisco representative in order to continue the use of the feature.
I hope this helps!
-Robert
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