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plex.tv link code . The Plex token is used to authenticate a device with your Plex server. When you are signed into your Plex Media Server, you are assigned a generated token. This token is used to authenticate your device with your Plex server. This replaces having to provide your user ID and password with each request you make to Plex. The Device Claiming Server allows users to claim devices and gateways in a secure manner. The Device Claiming Server takes care of checking verifying ownership and transferring the device or gateway from a source to a target security domain. For more information about claiming end devices, see Device Claiming.