[License-review] Request for Legacy Approval for the ICU License (as used by ICU 1.8.1 to ICU 57.1)

[Jeff Johnson]

Greetings,

I'm requesting that the ICU License be considered for Legacy approval as an OSI-approved license.  

Rationale:

The ICU License is used by the extremely popular decNumber library (https://speleotrove.com/decimal/), which is dual-licensed (with the other option being GPL - https://github.com/gcc-mirror/gcc/tree/master/libdecnumber).  The DPS8M simulator program is using the ICU License.  There are other major programs that redistribute ICU-licensed code such as Bloomberg COMDB2, IBM NetREXX, etc.

Currently, Debian and Red Hat allow this license. Red Hat via Fedora considers it a variant of the MIT License.  See https://fedoraproject.org/wiki/Licensing:MIT#Modern_style_(ICU_Variant). Code under this license is distributed with Android (https://chromium.googlesource.com/chromium/deps/icu/+/refs/heads/main/LICENSE). 

ICU-licensed code is included in more than 2,500 projects on GitHub - see https://github.com/search?q=%22COPYRIGHT+AND+PERMISSION+NOTICE%22+%22ICU+License%22&type=code.

The chances of decNumber being re-licensed by IBM is essentially zero (or I simply don't know who to talk to), which means that all code that derives from the ICU-licensed decNumber is not under an OSI approved license.  GitLab, for example, is not extending their free "Ultimate for Open Source Developers" for DPS8M and other projects due to the use of "non-OSI licensed" (ICU-licensed code) - they (and many others) will only allow explicitly listed OSI-approved licenses.  

The use of ICU Licensed code has come up as well in other projects, where there was confusion as to the status of the ICU-licensed code, and, wanting an OSI-approved license, decNumber code was replaced with other libraries, and finally reverted, a waste of time for all involved.

Distinguish:

The ICU License is very functionally similar to the MIT License.  Red Hat / Fedora considers the ICU license to be a variant of the MIT license.  It differs in four areas:

1) The grant of rights is explicit between Software and Documentation rather than both as a "work" (... provided that the above copyright notice(s) and this permission notice appear in all copies of the Software and that both the above copyright notice(s) and this permission notice appear in supporting documentation.)

2) It does not explicitly list "sublicense" as a right granted.

3) It disclaims all warranties, but the list of of these (including but not limited to) is slightly different (explicitly excluding only noninfringement of third party rights, etc).

4) It includes a non-publicity clause: "Except as contained in this notice, the name of a copyright holder shall not be used in advertising or otherwise to promote the sale, use or other dealings in this Software without prior written authorization of the copyright holder."

Legal review:

I am not aware of any published legal review of the specific text of this license.

Full Text:

Full text of the ICU License, with optional text bracketed:

```
COPYRIGHT AND PERMISSION NOTICE

Copyright (c) yyyy-yyyy copyright holder

[All Rights Reserved.]

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, provided that the above copyright notice(s) and this permission notice appear in all copies of the Software and that both the above copyright notice(s) and this permission notice appear in supporting documentation.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

Except as contained in this notice, the name of a copyright holder shall not be used in advertising or otherwise to promote the sale, use or other dealings in this Software without prior written authorization of the copyright holder.
```

Recommended proliferation category: 

I would consider this license to be a Legacy license - "Licenses that are redundant with more popular licenses" and not to be recommended for new projects.

--
Jeffrey H. Johnson
trnsz at pobox.com