[License-discuss] Changes made by derivative works
forums at david-woolley.me.uk
Thu Jan 31 10:20:29 UTC 2013
Gervase Markham wrote:
> If you are writing a license, please don't include a line like this.
> Depending on how you interpret it, it's either ineffective (because the
> next person can simply remove your notices as part of their change) or a
> pain in the behind (as your file fills up with notices which are best
> maintained in your source code management system anyway). This makes
> such lines in existing licenses far more honoured in the breach than the
The purpose of such clauses is not to track the provenance, but to
maintain the purity of the official version, so that forks cannot be
passed off as approved versions.
> The days of tracking code provenance via in-file comments are gone. And
> they are not missed IMO.
One of the key objectives of open source is code re-use. This means
that a file must be usable outside the context of the original
application, and therefore with a different, or no, source management
If you are going to rely on a source management system, you must insist,
in the licence, that any distribution of the code contains all the
source management meta-data. It is still standards practice to
distribute source as a single version tar.gz or tar.bz2, i.e. without
any of the meta data.
The meta data also often doesn't contain legal identity of the
modifieres, and doesn't distinguish between de mimis changes, and ones
where the modify owns copyright.
Requiring that the complete repository accompany the code would be a
real dampener on open source.
There may be compromises, but the less information you include in a
file, the more difficult it is to re-license it, once divorced from the
original source management system.
Incidentally, source management systems are not new technology. I would
succest that they pre-date the formalisation of the open source concept.
Emails are not formal business letters, whatever businesses may want.
RFC1855 says there should be an address here, but, in a world of spam,
that is no longer good advice, as archive address hiding may not work.
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