I might be able to but you are already on your way, branch off the references links there and look at open source (in the intelligence sense) of places like res

I might be able to but you are already on your way, branch off the references links there and look at open source (in the intelligence sense) of places like resumes and linkedin to see who is using what. Some permutation is used at the nucleus of card networks like visa, ACH, most public stock exchanges, and a lot of other financial instrument markets, as well as the systems of record for some of the largest banks and governments.