% 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/
#
# Copyright 1997-2024, American Registry for Internet Numbers, Ltd.
#

NetRange:       2607:4000:: - 2607:4000:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF
CIDR:           2607:4000::/32
NetName:        UW-IPV6-BLK1
NetHandle:      NET6-2607-4000-1
Parent:         NET6-2600 (NET6-2600-1)
NetType:        Direct Allocation
OriginAS:       AS73
Organization:   University of Washington (UWND)
RegDate:        2010-02-25
Updated:        2012-03-02
Comment:        University of Washington (noc@cac.washington.edu)
Ref:            https://rdap.arin.net/registry/ip/2607:4000::

OrgName:        University of Washington
OrgId:          UWND
Address:        4545 15th Ave NE
City:           Seattle
StateProv:      WA
PostalCode:     98105
Country:        US
RegDate:        
Updated:        2020-10-30
Ref:            https://rdap.arin.net/registry/entity/UWND

OrgAbuseHandle: UWSO-ARIN
OrgAbuseName:   University of Washington Security Operations
OrgAbusePhone:  +1-206-221-7000 
OrgAbuseEmail:  security@uw.edu
OrgAbuseRef:    https://rdap.arin.net/registry/entity/UWSO-ARIN

OrgNOCHandle: UW-NOC-ARIN
OrgNOCName:   University of Washington Networks and Distributed
OrgNOCPhone:  +1-206-221-6000 
OrgNOCEmail:  uw-noc@uw.edu
OrgNOCRef:    https://rdap.arin.net/registry/entity/UW-NOC-ARIN

OrgTechHandle: UW-NOC-ARIN
OrgTechName:   University of Washington Networks and Distributed
OrgTechPhone:  +1-206-221-6000 
OrgTechEmail:  uw-noc@uw.edu
OrgTechRef:    https://rdap.arin.net/registry/entity/UW-NOC-ARIN

RNOCHandle: OWU2-ARIN
RNOCName:   University, Of Washington
RNOCPhone:  +1-206-221-6000 
RNOCEmail:  noc@cac.washington.edu
RNOCRef:    https://rdap.arin.net/registry/entity/OWU2-ARIN

RAbuseHandle: UWSO-ARIN
RAbuseName:   University of Washington Security Operations
RAbusePhone:  +1-206-221-7000 
RAbuseEmail:  security@uw.edu
RAbuseRef:    https://rdap.arin.net/registry/entity/UWSO-ARIN

RTechHandle: OWU2-ARIN
RTechName:   University, Of Washington
RTechPhone:  +1-206-221-6000 
RTechEmail:  noc@cac.washington.edu
RTechRef:    https://rdap.arin.net/registry/entity/OWU2-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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