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Yes, the Meru 3200 controllers (and all Meru / Fortinet Wirleess LAN controllers for that matter), can locally bridge Wireless clients.
On the Meru/Controller platform you'll need edit the ESS profile (where the SSID is set) and set the dataplane mode from tunnelled (default) to Bridge.
Typically you will be bridding traffic to a local VLAN, so you will need to likely need to set the VLAN Policy to 'static VLAN only' and specify the VLAN tag ID.
With this configuration the Access Point will bridge Wireless clients that connect to the ESS profile straight to the local switch where the AP is connected, therefore you will need to ensure that the switch's ports are configured (tagged) for the VLAN you're bridging to.
Hope this helps.