For a fair number of torrents I'm dealing with (qBittorrent 3.3.7 here), I see a number of entries in the "Peers" list (it apparently only shows peers that are currently connected) with
client_test/220.127.116.11 in the "Client" column.
They appear to stay connected for extended time but not participate in uploading/downloading - and probably skew the numbers in tracker stats, too. They are predominantly US IPs while the "normal" peers for these torrents tend to be from the former Eastern bloc.
Is there any information/investigations on them out there? Are they fakes and should be banned/reported or something?