Question about PHP Licence and it's future!

Hi! I have asked myself a question. After I saw, that SAP will no more release future Versions of their open source Database MaxDB under the GPL License, I have asked myself either if this could happen with PHP. Who owns PHP? Is it Zend Technologies or the PHP Group itself? "Who" is the PHP Group and what makes the PHP Group? Who guaranties that future Versions of PHP stays open source and are being released under the Terms of the General Public Licenses? Can future Versions from one day to the other no more being released under the GPL, only under a closed source license? Let us say, PHP would be distributed for several architectures only in binary forms and the PECL modules stay open source. These questions are for me very importand according to an commercial product which will be planed, designed, written and sold commercially. We are pendling between Ruby, Python and PHP5. Only the point "written" is unclear. for any answer Thank you very much Tamer Higazi