Smart Group with multiple "Search in" Groups

I intend to build a Smart Group with a condition like:

From Group-A or Group-B or Group-C
AND
tag is-not ‘uploaded’

Since I can only specify one Search-In field I don’t understand how to achieve this.
I could probably put the 3 Groups as Sub-Groups in a common Group but I’d rather keep them apart. Is there some trick to achieve this?

If you are using Group Tags (the Group icons will be yellow and the Tags will be gray), you could construct a Smart Group like this…
MultiGroupSearch.jpgThis would show any files in Groups 2013 or (as specified by using the ANY argument) 2014 that do not have the Tag “uploaded”.

Oh cool feature didn’t know about “Group Tags” yet (newbie here).

Just for reference the details are described here http://blog.devontechnologies.com/2012/03/wednesday-tip-why-excluding-a-group-from-tagging-can-be-useful/

I switched it on and now have quite a lot of “duplicate” tags (different case in groups and tags) — which is a sign I should keep it on — need to do a bit cleaning up my tags now I think.

Thanks for the tip