I am staff on a few
trackers ; and yes when we find
ratio cheaters and the like we send all details to a list of
trackers for investigation, on the list is
HDB,
HDT,
PTP,
BTN,
MTV, PHD group, Blu,
AR and a bunch of others .
This is done for bad cheaters and traders/inviters only, unlikely to be done for members on the invite tree, but would be done with the invitee in this case.
But main
tracker I work for is going to limit number of invites available to be issued to X invites in a year. This is largely to stop traders/sellers.