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# License and Copyright
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*Omnis enim res, quae dando non deficit, dum habetur et non datur, nondum habetur, quomodo habenda est.*

"For if a thing is not diminished by being shared with others, it is not rightly owned if it is only owned and not shared."

— Saint Augustine, [*De Doctrina Christiana*](http://www.ccel.org/a/augustine/doctrine/doctrine.html), *c.* 396 AD.

MIT Photonic-Bands is copyright © 1999–2019, Massachusetts Institute of Technology.

MPB is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this library; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. You can also find it on the GNU web site:


[http://www.gnu.org/copyleft/gpl.html](http://www.gnu.org/copyleft/gpl.html)

The file `minpack2-linmin.c` was derived from the [MINPACK-2](ftp://info.mcs.anl.gov/pub/MINPACK-2/) package. It is copyright © 1996 by [Jorge J. Moré](http://www-unix.mcs.anl.gov/~more/), who has graciously granted us permission to distribute it along with MPB under the GNU General Public License.

As a clarification, we should note that Scheme control (`ctl`) files, written by the user (i.e. not containing code distributed with MPB) and loaded at runtime by MPB, are *not* considered derived works of MPB and do *not* fall thereby under the restrictions of the GNU General Public License.

In addition, all of the example Scheme code in this manual, as well as the example ctl files in the `mpb/examples/` directory, may be freely used, modified, and redistributed, without any restrictions. The warranty disclaimer still applies, of course.