Microsoft put emphasis on their claims at this months quarterly ARB meeting (OpenGL Architectural Review Board) as can be read in the meetings notes here. The confusion centers about API parts called vertex programming and fragment shading which allow game and graphic developers greater freedom on 3D effects such as lighting. Read more... OpenGL owes its current success to an unrestrictive licensing system, which allows developers to write to the API without a license. It also carries no royalty fees. This benefits the makers of graphics hardware, who would otherwise be stuck either paying royalties to patent holders or supporting a number of different proprietary standards. But the system only works if companies that hold relevant intellectual property agree not to press their claims, in return for the benefits of a free, unified standard. One trouble is that Microsoft, which doesn't make graphics hardware and isn't heavily involved in non-Windows platforms, has little vested interest in supporting an open, cross-platform standard such as OpenGL, according to Matthew Warren, a partner at law firm Bristows who specializes in IP. The origin of Microsoft's patents is unclear, but the company has acquired intellectual property from SGI, Nvidia, ATI Technologies, Intel and others, according to industry observers. "They've just been picking it up everywhere," said Jon Peddie, head of consulting firm Jon Peddie Research. "They have a huge library of intellectual property." There you have it. Microsoft could dominate the graphics API if their claims are legal. And as far as we know M$ - do you believe they will support a free sort of 'open-source' standard? Cast your vote on your favourite graphics API in the attached poll on the right hand side. Source: Partly ZDNet