In article <cv3ce4-utc.ln1@g...>,
Simon Brooke  <simon@j...> wrote:

>> I want to give it away for free. But, in order to do that, I have to
>> ensure that it will stay free.

>Seriously, if you want that, the solution is one of:
>
>The GPL <URL:http://www.gnu.org/licenses/gpl.html> - not designed for this
>sort of thing, but with real legal teeth.

Regardless of whether the GPL is appropriate for protecting a
specification, the OP apparently wants to prevent others from
extending his work, which is contrary to the spirit of the GPL.  While
I sympathise with the aim of preventing the likes of Microsoft from
"embracing and extending", doing this by restricting what ordinary
users can do would certainly put me off using it.

A less extreme approach is to have the definition require that
non-conformant documents not be accepted.  This is what XML does, so
that (for example) an extension that allowed </> end tags would not be
able to claim conformance with the XML specification.

-- Richard
-- 
"Consideration shall be given to the need for as many as 32 characters
in some alphabets" - X3.4, 1963.