tfkiss - Notes on Copyright and Licensing
=========================================

This file documents the copyright status of tfkiss, the licensing
terms it is distributed under, and the reasoning behind continuing
to distribute this modified version. It is provided in the interest
of transparency for packagers and users.

See doc/copyrght.txt and doc/alas.eng for the original license texts,
which are distributed unmodified with this software.


1. Copyright holders
--------------------

tfkiss is a layered work with several rights holders:

  - TheFirmware (TF), the AX.25 Layer 2 implementation at the core of
    this program, is Copyright (c) 1988-1996 NORD><LINK e.V., a German
    registered association (eingetragener Verein).

  - The Unix port, the autoconf build system, and extensive bug fixes
    are the work of Berndt Josef Wulf, VK5ABN SK.

  - Solaris support was contributed by Hans Mayer, OE1SMC.

  - Additional fixes were contributed by Matthias Hensler, WS1AC.

  - DragonFly BSD support and DESTDIR install support were contributed
    via the NetBSD pkgsrc packaging system (2005 and 2009).

  - 64-bit correctness fixes, ANSI C modernization, and the current
    autoconf/automake build system are the work of Chris Maness, KQ6UP.

All prior copyright notices have been preserved in the source code and
in the program's startup banner, as required.


2. License terms
----------------

doc/copyrght.txt states that the software may be used free of charge
for private, non-commercial use by radio amateurs; that the NORD><LINK
copyright notice may not be removed from either the source or the
startup message of the compiled program; and that the terms of the
license distributed with each copy of the software apply, referring to
ALAS (doc/alas.eng, doc/alas.txt).

ALAS -- the Allgemeine Lizenz fuer Amateurfunk Software (General
Licence for Amateur Radio Software) -- permits use, copying,
modification, and distribution for non-commercial purposes, and places
duties on anyone modifying or distributing the software. Section 4.5
requires that a modifier clearly indicate their name and address and
the fact of modification, and distribute the complete source code or
provide it on demand at cost.

doc/copyrght.txt additionally states that distribution of modified
versions is permitted only with the prior consent of NORD><LINK. This
provision is in tension with the ALAS terms that the same document
directs the reader to, and which ALAS itself applies to all software
distributed under it.


3. Compliance
-------------

This distribution complies with the ALAS terms in full:

  - Non-commercial. This software is distributed free of charge and
    is not sold, bundled with any commercial product, or used for
    commercial purposes.

  - Attribution. The modifier is identified by name, callsign, and
    email address in this file, in README, and in CHANGES.

  - Modification disclosed. All changes are itemized by version and
    attributed by author in CHANGES.

  - Complete source. Full source code is distributed with every
    release and is publicly available at
    https://github.com/kq6up/tfkiss

  - Copyright notices preserved. The NORD><LINK copyright appears
    unchanged in the source and in the program's startup banner, as
    do the notices of all subsequent contributors.

  - Original license texts included and unmodified, and installed
    with the package.


4. On obtaining consent, and on relicensing
-------------------------------------------

The consent provision in doc/copyrght.txt cannot be satisfied, because
no rights holder can be located:

  - NORD><LINK e.V. appears to be dissolved. Its website, nordlink.org,
    is no longer operating and the domain is offered for sale. No
    successor organization or contact has been identified.

  - Berndt Josef Wulf, VK5ABN, is a Silent Key.

Relicensing the work under a modern free software license such as the
GNU GPL is likewise not possible. It would require the agreement of
every rights holder listed in section 1, including a dissolved German
association and the estate of a deceased author. Furthermore, under
German copyright law (UrhG Sec. 29), copyright itself is inalienable
and cannot be transferred except by inheritance; only rights of use may
be granted, and then only by a rights holder able to grant them.

This software is therefore, in practical terms, an orphaned work. It is
maintained and distributed here in good faith, in full compliance with
the ALAS terms that doc/copyrght.txt directs the reader to, and in a
manner consistent with the evident intent of the original authors: that
this software remain freely available to radio amateurs for
non-commercial use, with its source code open and its authorship
acknowledged.

Precedent for this treatment exists within the NetBSD pkgsrc
collection, which has distributed a patched tfkiss since 2005 and
distributes other amateur radio software of similar provenance under
the license marker "generic-nonlicense" together with a restriction
against commercial use.


5. Standing offer
-----------------

If any rights holder, heir, successor in interest, or authorized
representative of NORD><LINK e.V. or of any contributor named above
wishes to discuss this distribution, please make contact. Any
reasonable request, including a request to cease distribution, will
be honored promptly.

    Chris Maness, KQ6UP
    christopher.maness@gmail.com
    https://github.com/kq6up/tfkiss


6. Disclaimer
-------------

This document records the maintainer's good-faith understanding of the
copyright situation. It is not legal advice and does not constitute a
legal opinion. The software is provided without warranty of any kind,
as stated in the original license texts.
