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

#
# ARIN WHOIS data and services are subject to the Terms of Use
# available at: https://www.arin.net/resources/registry/whois/tou/
#
# If you see inaccuracies in the results, please report at
# https://www.arin.net/resources/registry/whois/inaccuracy_reporting/
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# Copyright 1997-2024, American Registry for Internet Numbers, Ltd.
#

NetRange:       146.203.0.0 - 146.203.255.255
CIDR:           146.203.0.0/16
NetName:        MSSMEDU-1
NetHandle:      NET-146-203-0-0-1
Parent:         NET146 (NET-146-0-0-0-0)
NetType:        Direct Allocation
OriginAS:       AS11452
Organization:   Mount Sinai School of Medicine (MSSM)
RegDate:        1991-02-28
Updated:        2021-12-14
Ref:            https://rdap.arin.net/registry/ip/146.203.0.0

OrgName:        Mount Sinai School of Medicine
OrgId:          MSSM
Address:        One Gustave L. Levy Place
Address:        Mailstop 1102
City:           New York
StateProv:      NY
PostalCode:     10029-6574
Country:        US
RegDate:        1991-02-28
Updated:        2023-06-20
Ref:            https://rdap.arin.net/registry/entity/MSSM

OrgTechHandle: AP412-ARIN
OrgTechName:   Pizzimenti, Andrew 
OrgTechPhone:  +1-212-241-4929 
OrgTechEmail:  andrew.pizzimenti@mssm.edu
OrgTechRef:    https://rdap.arin.net/registry/entity/AP412-ARIN

OrgAbuseHandle: AP412-ARIN
OrgAbuseName:   Pizzimenti, Andrew 
OrgAbusePhone:  +1-212-241-4929 
OrgAbuseEmail:  andrew.pizzimenti@mssm.edu
OrgAbuseRef:    https://rdap.arin.net/registry/entity/AP412-ARIN

OrgNOCHandle: AP412-ARIN
OrgNOCName:   Pizzimenti, Andrew 
OrgNOCPhone:  +1-212-241-4929 
OrgNOCEmail:  andrew.pizzimenti@mssm.edu
OrgNOCRef:    https://rdap.arin.net/registry/entity/AP412-ARIN

OrgTechHandle: GUNTH50-ARIN
OrgTechName:   Gunther, Doug 
OrgTechPhone:  +1-212-814-4541 
OrgTechEmail:  doug.gunther@mountsinai.org
OrgTechRef:    https://rdap.arin.net/registry/entity/GUNTH50-ARIN

OrgNOCHandle: CRUZO-ARIN
OrgNOCName:   Cruz, Orquidia 
OrgNOCPhone:  +1-212-241-4925 
OrgNOCEmail:  Orquidia.Cruz@mssm.edu
OrgNOCRef:    https://rdap.arin.net/registry/entity/CRUZO-ARIN

RNOCHandle: NETWO2964-ARIN
RNOCName:   Network Operations
RNOCPhone:  +1-212-241-7091 
RNOCEmail:  abuse@mssm.edu
RNOCRef:    https://rdap.arin.net/registry/entity/NETWO2964-ARIN

RAbuseHandle: NETWO2964-ARIN
RAbuseName:   Network Operations
RAbusePhone:  +1-212-241-7091 
RAbuseEmail:  abuse@mssm.edu
RAbuseRef:    https://rdap.arin.net/registry/entity/NETWO2964-ARIN

RTechHandle: AP412-ARIN
RTechName:   Pizzimenti, Andrew 
RTechPhone:  +1-212-241-4929 
RTechEmail:  andrew.pizzimenti@mssm.edu
RTechRef:    https://rdap.arin.net/registry/entity/AP412-ARIN

#
# ARIN WHOIS data and services are subject to the Terms of Use
# available at: https://www.arin.net/resources/registry/whois/tou/
#
# If you see inaccuracies in the results, please report at
# https://www.arin.net/resources/registry/whois/inaccuracy_reporting/
#
# Copyright 1997-2024, American Registry for Internet Numbers, Ltd.
#

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