Re: Legal Question: Copyrights

[ka@socrates.hr.att.com (Kenneth Almquist)]

s0222353@moncol.monmouth.edu (DEAN RUNZEL) queries:
>   I've noticed that almost everything in the PAL and other Ada repositories
> include some kind of copyright notice. Usually this is pretty standard and I
> think based on some standard used by GNU. In the notice, the authors usually
> give permission to reuse the asset provided the notice appears unchanged.
> Now, my question is:
>
>   If I download a package and then make changes to some, but not all, of the
> procedures, etc. contained in the package to create a new asset, do I have to
> include the original copyright notice or should I create a new notice but
> acknowledge the previous work in some other way (for example: Based on 
> previous work performed by Mr. X copyright 1994)?

The resulting package is a "derived work" based on the original package.
This means that both you and the original author have a copyright on the
package.  Holding a copyright on a work gives you the legal right to
restrict what other people can do with the work.  That's all.  Even though
you hold a copyright on the derived work, you must abide by any usage
restrictions imposed by the original author, including the requirement
that the original notice remain intact.  What you can do is to add your
own copyright message below the original, along the lines of

  /* Modifications copyright 1995 by XXX.
     Permission to freely reuse or modify this work is granted by XXX
     provided that [INSERT USAGE RESTRICTIONS HERE]. */

There is no need to add your own copyright notice unless you want to
restrict usage in some way, but you probably want to add some sort of
comment to the source so that people won't confuse it with the original
package.

>   So, exactly how much must I change the original product in order to qualify
> for a new copyright? 

Any change qualifies for a new copyright, but it doesn't invalidate any
existing copyrights.  (Exception:  if you change the product to the point
where it no longer has any real relationship to the original product,
then the copyright on the original product may no longer apply.)
					Kenneth Almquist


Disclaimer:  I am not a lawyer.