% APNIC found the following authoritative answer from: whois.ripe.net

% This is the RIPE Database query service.
% The objects are in RPSL format.
%
% The RIPE Database is subject to Terms and Conditions.
% See https://docs.db.ripe.net/terms-conditions.html

% Note: this output has been filtered.
%       To receive output for a database update, use the "-B" flag.

% Information related to '2a01:5740:1000:2500::/56'

% Abuse contact for '2a01:5740:1000:2500::/56' is 'abuse@selfnet.at'

inet6num:       2a01:5740:1000:2500::/56
netname:        Plakativ-Failover-v6
descr:          Plakativ Werbetechnik
country:        AT
admin-c:        SH5704-RIPE
tech-c:         SH5704-RIPE
status:         ASSIGNED
mnt-by:         MNT-SELFNET
mnt-lower:      MNT-SELFNET
mnt-routes:     MNT-SELFNET
created:        2014-03-26T15:21:20Z
last-modified:  2014-03-26T15:21:20Z
source:         RIPE

role:           SelfNet Hostmaster
address:        Kugygasse 18
address:        1130 Vienna
address:        Austria
abuse-mailbox:  abuse@selfnet.at
admin-c:        TS6253-RIPE
tech-c:         TS6253-RIPE
nic-hdl:        SH5704-RIPE
mnt-by:         MNT-SELFNET
created:        2012-01-23T15:53:15Z
last-modified:  2023-09-25T14:21:20Z
source:         RIPE # Filtered

% Information related to '2a01:5740::/32AS57763'

route6:         2a01:5740::/32
descr:          Selfnet Internet Ges.m.b.H.
origin:         AS57763
mnt-by:         MNT-SELFNET
created:        2013-03-14T11:43:05Z
last-modified:  2021-05-12T06:51:21Z
source:         RIPE

% This query was served by the RIPE Database Query Service version 1.114 (SHETLAND)

Search for
IP address lookups			Miscellaneous queries
-l	1st level less specific		-i	Inverse attributes	None admin-c admin-c,tech-c,zone-c author cross-mnt cross-nfy local-as mbrs-by-ref member-of mnt-by mnt-lower mnt-nfy mnt-routes notify nserver origin person referral-by rev-srv sub-dom tech-c upd-to zone-c
-L	All less specific		-T	Object types	All as-block as-set aut-num domain filter-set inet-rtr inet6num inetnum irt key-cert mntner peering-set person role route route-set rtr-set
-m	1st level more specific
-M	All more specific		Query hints Include "AS" in front of an AS number. Example: AS4808 Include "-t" (template only) or "-v" (template and description) in front of an object name to view the template Example: -t inetnum
-x	Exact match only
-d	Associated reverse domain