% 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 '83.103.96.128 - 83.103.96.135'

% Abuse contact for '83.103.96.128 - 83.103.96.135' is 'abuse@fastweb.it'

inetnum:        83.103.96.128 - 83.103.96.135
netname:        FASTWEB-Vimercati-Spa
descr:          Vimercati Spa public subnet
country:        IT
admin-c:        MB9567-RIPE
tech-c:         IRS2-RIPE
status:         ASSIGNED PA
mnt-by:         FASTWEB-MNT
remarks:        In case of improper use originating from our network,
remarks:        please mail customer or abuse@fastweb.it
created:        2005-02-15T17:59:43Z
last-modified:  2008-08-18T08:24:56Z
source:         RIPE

person:         ip registration service
address:        Via Caracciolo, 51
address:        20155 Milano MI
address:        Italy
phone:          +39 02 45451
fax-no:         +39 02 45451
nic-hdl:        IRS2-RIPE
mnt-by:         FASTWEB-MNT
remarks:
remarks:        In case of improper use originating from our network,
remarks:        please mail customer or abuse@fastweb.it
remarks:
created:        2001-12-18T12:06:41Z
last-modified:  2008-02-29T14:09:58Z
source:         RIPE # Filtered

person:         Massimo Branco
address:        VIMERCATI SpA
address:        PTA Brera 24/6
address:        20100 Milano Mi
address:        Italy
phone:          +39 02 381941
fax-no:         +39 02 3538485
nic-hdl:        MB9567-RIPE
created:        2005-02-04T15:27:28Z
last-modified:  2020-06-03T11:35:02Z
source:         RIPE # Filtered
mnt-by:         FASTWEB-MNT

% Information related to '83.103.64.0/18AS12874'

route:          83.103.64.0/18
descr:          Fastweb Networks block
origin:         AS12874
mnt-by:         FASTWEB-MNT
remarks:
remarks:        In case of improper use originating from our network,
remarks:        please mail customer or abuse@fastweb.it
remarks:
created:        2008-02-05T12:06:22Z
last-modified:  2008-02-05T12:06:22Z
source:         RIPE

% This query was served by the RIPE Database Query Service version 1.120 (SHETLAND)