A user has posted a bunch of answers about "ATG" this, that and the other. Never heard of them , and nor has google.
There appears to be a set of spammy posts on Flickr about "ATG" like this
https://www.flickr.com/groups/2497488@N21/discuss/72157639746143256/
and, particularly this, all originating from one user.
https://www.flickr.com/groups/canoneos5dmarkii/discuss/72157625911050907/
No idea what's going on but frankly, it smells....