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

% [whois.apnic.net]
% Whois data copyright terms    http://www.apnic.net/db/dbcopyright.html

% Information related to '43.251.52.0 - 43.251.55.255'

% Abuse contact for '43.251.52.0 - 43.251.55.255' is 'netadmin@buroserv.com.au'

inetnum:        43.251.52.0 - 43.251.55.255
netname:        BUROSERV-AP
descr:          Buroserv Australia Pty Ltd
descr:          70-76 Alexander Street
country:        AU
org:            ORG-BAPL2-AP
admin-c:        BAPL3-AP
tech-c:         BAPL3-AP
abuse-c:        AB1023-AP
status:         ALLOCATED PORTABLE
remarks:        --------------------------------------------------------
remarks:        To report network abuse, please contact mnt-irt
remarks:        For troubleshooting, please contact tech-c and admin-c
remarks:        Report invalid contact via www.apnic.net/invalidcontact
remarks:        --------------------------------------------------------
mnt-by:         APNIC-HM
mnt-lower:      MAINT-BUROSERV-AU
mnt-routes:     MAINT-BUROSERV-AU
mnt-irt:        IRT-BUROSERV-AU
last-modified:  2020-06-22T05:17:48Z
source:         APNIC

irt:            IRT-BUROSERV-AU
address:        7/80, Pacific Highway, North Sydney, NSW, 2060, Australia
e-mail:         netadmin@buroserv.com.au
abuse-mailbox:  netadmin@buroserv.com.au
admin-c:        BAPL3-AP
tech-c:         BAPL3-AP
auth:           # Filtered
remarks:        netadmin@buroserv.com.au was validated on 2025-07-22
mnt-by:         MAINT-BUROSERV-AU
last-modified:  2025-11-18T00:29:10Z
source:         APNIC

organisation:   ORG-BAPL2-AP
org-name:       Buroserv Australia Pty Ltd
org-type:       LIR
country:        AU
address:        Level 5
address:        12 Help Street
address:        Australia
phone:          +611300726210
e-mail:         NetAdmin@buroserv.net.au
mnt-ref:        APNIC-HM
mnt-by:         APNIC-HM
last-modified:  2023-09-05T02:16:24Z
source:         APNIC

role:           ABUSE BUROSERVAU
country:        ZZ
address:        7/80, Pacific Highway, North Sydney, NSW, 2060, Australia
phone:          +000000000
e-mail:         netadmin@buroserv.com.au
admin-c:        BAPL3-AP
tech-c:         BAPL3-AP
nic-hdl:        AB1023-AP
remarks:        Generated from irt object IRT-BUROSERV-AU
remarks:        netadmin@buroserv.com.au was validated on 2025-07-22
abuse-mailbox:  netadmin@buroserv.com.au
mnt-by:         APNIC-ABUSE
last-modified:  2025-07-22T23:38:27Z
source:         APNIC

role:           Buroserv Australia Pty Ltd administrator
address:        LEVEL 2, 9 HELP STREET, CHATSWOOD, NSW, 2067
country:        AU
phone:          +611300726210
+               61288803450
fax-no:         +61288803450
e-mail:         netadmin@buroserv.net.au
admin-c:        NA630-AP
tech-c:         NA630-AP
nic-hdl:        BAPL3-AP
mnt-by:         MAINT-BUROSERV-AU
last-modified:  2020-06-15T22:58:24Z
source:         APNIC

% Information related to '43.251.52.0/24AS38835'

route:          43.251.52.0/24
origin:         AS38835
descr:          Buroserv Australia Pty Ltd
                Level 2
                9 Help Street
                Australia
mnt-by:         MAINT-BUROSERV-AU
last-modified:  2019-12-09T23:10:43Z
source:         APNIC

% This query was served by the APNIC Whois Service version 1.88.36-SNAPSHOT (WHOIS-AU5)