Localady, Hammybee and others contributed the only approach I know of which is to do a search engine search for the specific sailing to see if a result pops up with the cruise associated with a specific organization.
The issue really pertains to large groups where there is a possibility that the group might intrude on the enjoyment of the cruise by individual passengers, not to non-intrusive smaller groups.
If you are aware of a site or other source where such info can be obtained, please post details here.
If you have specific, verifiable information about a specific group booking on a specific cruise, however, please post that information of the Roll Call thread for that cruise and not here.
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