icu4c/source/data/cldr-icu-readme.txt

# Copyright (C) 2016 and later: Unicode, Inc. and others.
# License & terms of use: https://www.unicode.org/copyright.html
# Copyright (C) 2010-2014, International Business Machines Corporation and others.
# All Rights Reserved.                  

This has been replaced by the markdown file
../../../docs/processes/cldr-icu.md 
which is best viewed as
https://unicode-org.github.io/icu/processes/cldr-icu.html