Hi @MarketAxess,
You were on the right path. The documentation for this one is here (on 9.1 as per your docs link in the original post).
The multi-move option is one of the options for action, when making XML API calls of type config. Where move is another option, you would not combine them together. Others include set, edit, delete etc:
What worked for me and hopefully for you, to move an address object from shared to a DG, would be:
https://{{host}}/api/?key={{key}}&type=config&action=multi-move&xpath=/config/devices/entry[@name='localhost.localdomain']/device-group/entry[@name='{{device-group-name}}']/address&element=<selected-list><source xpath="/config/shared/address"><member>{{address-object-name}}</member></source></selected-list><all-errors>yes</all-errors>
Hope that helps!
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