When the wake-word “OK Webex” is recognized by the device, the listening mode that is available on it will become active. The listening mode may be turned on and off using the wake-word. Otherwise, the mode for listening will be turned off. When the Webex Assistant pane is active and the “Listening” indicator is visible on the screen, the microphone will only transmit audio from the device when it is being used to listen in on the conversation.
The device is responsible for the collection of the voice data, which is subsequently transmitted over the network to the speech recognition service. The information is not kept anywhere and is just utilized while it is being processed. The voice data that is streamed to the speech recognition service is encrypted before it is delivered over HTTPS to the service.
You may read addendum five in this privacy data sheet if you want further information about the privacy of your device when using Webex Assistant.