Re: Changing a software license

[John Hasler <john@dhh.gt.org>]

Matt Yanchyshyn writes:
> Say I write some origianl code (that does not use any external libraries,
> programs or otherwise) and license it under the GPL or BSD license.  As
> the original author of that code, can I change its license later on or it
> it legally locked to its original public designation?

You don't license the code in the abstract sense.  You license each
individual _copy_ that you distribute under the terms of the license that
you attach to it.  Thus you can send out the first copy under the GPL, the
second under the BSD, the third under the EULA, etc.

> More specifically, if this code is originally licensed as BSD and I
> decide to change it to GPL, will all those who used my code in their
> programs be forced to GPL-ify their work as well?

Of course not.  If you license a copy of your program to me under the terms
of the BSD, then that's that.  What terms you choose to attach to a other
copies licensed to other people is irrelevant.

> Likewise, if I move from [GPL to BSD], may developpers previously under
> the GPL restrictions start to take advantage of the BSD license's extra
> freedoms?

Only after they acquire BSD licensed copies.
-- 
John Hasler
john@dhh.gt.org (John Hasler)
Dancing Horse Hill
Elmwood, WI