selling GPL sources

[Ben Tilly]

On 9/19/05, Guilherme C. Hazan <guich at superwaba.com.br> wrote:
> Hi Ian,
> 
>  >> I'm aware of a program that uses the GPL license and the author made
>  >> the binaries free but not the sources. He asks a fee for the sources
>  >> (about 100usd).
>  >>
>  >> Is this legal or is he infringing the GPL license?
>  >
>  > The GPL permits "a charge no more than your cost of physically
>  > performing source distribution."  If his cost is 100USD or greater,
>  > than he is not infringing.  If his cost is less than 100USD, then he
>  > is infringing.
> 
> Sorry, isnt the opposite? If it is 100 or less, then its ok, otherwise,
> if is more than 100, then is illegal?

Ian had it right the first time.  If he is charging $100 and his costs
are $1000, then he is charging no more than his cost of physically
performing source distribution.  If he is charging $100 and his costs
are $10, then he is charging more than his cost of physically
performing source distribution.

By the way, as far as I know nothing stops someone from choosing to
distribute source in a particularly expensive and inconvenient way, as
long as it is on a medium customarily used for software interchange. 
For instance I might send a stack of CDs, each of which has 5 bytes of
source code.  If I have a reasonable amount of source code, this could
become prohibitively expensive indeed!

Of course once one person has received the source, they are free to
re-release in a more convenient form.

Cheers,
Ben