
====== gEDA Licensing ======

All software components of gEDA/gaf are released under the 
[[ http://www.gnu.org/licenses/old-licenses/gpl-2.0.html | GNU General Public
License (GPL) version 2 or later]].   However, some confusion exists about
the schematic symbols.  What license do they use? Will GPL symbols
"infect" your design, thereby requiring you to release your design to
the public? If you modify the symbols,  must you release the modified
versions under the GPL?  

The goal of the gEDA Project is to provide an open-source EDA Suite
which may be used for non-commercial as well as commercial projects.
Our tools are aimed for use by students, hobbyists, educators, consultants,
 and -- yes -- corporate engineers.  We are not interested
in exerting any control over your designs, or forcing you to reveal
proprietary information contained in your designs.

Symbols are similar to the font files used in document
processing software -- they are graphical objects used to express your
ideas.  We want you to retain control of your own ideas (your design),
while the gEDA Project retains a say in how you redistribute the
symbols themselves.

There are three ways a symbol might be distributed:

  - As part of a symbol library, or individually as a .sym file (i.e. as a symbol itself).
  - Embedded in a .sch file (i.e. part of the soft, or editable copy of a design).
  - The resulting graphical expression on a schematic diagram (i.e. as part of the hard, or non-editable copy of a design).

There is a distinction between cases 1 and (2, 3).  In case 1, the
object of interest is the symbol library (or individual symbol)
itself.  In case (2, 3), the object of interest is the design.
Some label case 1 "distribution", and case (2, 3) "use" of the symbol.

Our goals for the symbols are:

  * We wish to distribute the symbols under a licencing scheme which encourages that you give back to the community if you redistribute the the symbols themselves -- whether modified or unmodified.  This is case 1 distribution.  The GPL ensures this.

  * We wish to specifically prohibit anybody from building gEDA's symbols into their *software* products, and then place restrictions on how the resulting product may be used.  If you bundle gEDA symbols-- whether modified or unmodified -- into your software and then distribute it, then you must allow for the software's (and symbols') continued redistribution under the GPL.  Again, this is case 1 distribution; the GPL ensures this.

  * However, we do not wish to "infect" your *electronic* design, or force you to release your proprietary design information if you use or embed gEDA symbols in your design.  This is case (2, 3) use.

The Free Software Foundation has recognized a possible conflict of
the base GPL with the use of fonts -- and, by analogy, symbols used in
case (2, 3).  Their solution is to use an exemption clause in the GPL
which you explicitly insert for fonts.  Read about it here:

[[http://www.fsf.org/licensing/licenses/gpl-faq.html#FontException | http://www.fsf.org/licensing/licenses/gpl-faq.html#FontException]]

Therefore, using this as a template, all symbols released with
gEDA/gaf are covered under the GPL with the following exception clause:

  As a special exception, if you create a design which uses this symbol,
  and embed this symbol or unaltered portions of this symbol into the
  design, this symbol does not by itself cause the resulting design to
  be covered by the GNU General Public License. This exception does not
  however invalidate any other reasons why the design itself might be
  covered by the GNU General Public License. If you modify this
  symbol, you may extend this exception to your version of the
  symbol, but you are not obligated to do so. If you do not
  wish to do so, delete this exception statement from your version.

The idea is that case 1 redistribution is covered under the GPL, but
distribution of your design (case (2, 3) is exempt from the GPL.
This is the scheme which the gEDA Project wishes to use for symbol
distribution and use.
