[License-discuss] Changes made by derivative works

[Ben Reser]

On Wed, Jan 30, 2013 at 12:48 AM, Prashant Shah <pshah.mumbai at gmail.com> wrote:
> I am looking towards the copyright point of view.

Still not sure what objective you are trying to serve.  By saying the
copyright point of view do you mean you just want to keep track of the
copyright owners?  I'm going to assume that is what you mean for the
rest of this email.  If it isn't then you probably should be clearer
about what your objective is.

> In majority of cases the version control system used has the log of
> who submitted the code. Only if there are major changes then it might
> be necessary to include that in the file itself. How does one put that
> point across.

I think you're only thinking within the confines of an open source
project where someone submits code that goes into the projects version
control system.  With a license like this you may have forked versions
with modifications that may or may not have source code available for
them.  Even if the source code is available there's no guarantee that
the version control system (if any) used by the modifier is publicly
accessible.  Even if the version control system is publicly accessible
there's no guarantee that you can find the version control system that
matches with the distribution that you have.

If you want to be sure that you can identify the copyright holder of
modifications I don't think there's an easy way to get rid of any book
keeping requirement on the actual distributed files. Given that the
modifications do not automatically fall under the same license, it can
make it difficult to find modifications you want online and bring them
into your project if the identity of the modifier is not clear.

This clause is viewed as burdensome by some when I don't think in
practice it really is.  Remember you only have to say you modified the
file and identify yourself.  There's no requirement to describe your
changes.  If you're distributing source and using a version control
system it should be easy to automate marking files that have been
modified.  If you're distributing object forms it shouldn't be hard to
include something in the object that says you made modifications, e.g.
if the object is executable wherever the copyright notice appears note
that this is a modified version.  The only place I think that it's
particularly burdensome is if you're distributing libraries, since I
have no idea what would constitute a prominent notice on the actual
file.  ELF has a comment section you could use, but I'd be hard
pressed to characterize it as prominent notice.