Raymarine, AIS, C-120, C-70

[capacolla]

Forum,
I have a standard horizon AIS enabled VHF radio in the cabin, it's hooked up to a Raymarine C-120 MFD. Communication is perfect, the VHF gets is GPS fix from the MFD and in return the MFD gets target information.

The C-70 is at the helm. I was under the impression that if I supplied the C-120 with NEMA information from the radio, that it would share the data with C-70. This isn't the case. Any help would be appreciated.