The Open Design Alliance is an association of software developers and users committed to promoting open, industry-standard formats for the exchange of CAD data.
Formerly known as the OpenDWG Alliance, the Open Design Alliance is a non-profit membership-based consortium. Commercial software developers pay an annual membership fee to belong to the Alliance. End-users (both individuals and companies) pay no membership fees at all. Membership in the Alliance is available on a level playing field basis, with all members at the same level agreeing to the same membership terms.
AutoCAD DWG/DXF/DWF:
OpenDWG is based on the DWG format used in AutoCAD, as developed and sold by Autodesk. While OpenDWG is designed to provide as near to perfect compatibility with DWG as is possible, it has several advantages that have made it a safe choice for even mission-critical applications. First and foremost, it is documented, with no hidden encryption, and no obfuscation. Second, it is supported, with a dedicated team of technical professionals focused on fixing any problems that may crop up from time to time. Third, our OpenDWG software libraries are clean, written in object-oriented C++, and designed to impress even the most fastidious commercial software developers. And fourth, our OpenDWG software libraries are updated, providing compatibility with all versions of DWG from 2.5 to 2008. (Our OpenDWG libraries also support DXF and DWF, using the same API, and with the same high-quality and attention to detail.)
Bentley MicroStation DGN:
OpenDGN is based on specification published by Bentley Systems, and is compatible with MicroStation. Bentley Systems, a leading supplier of CAD software for architecture, plant & process, and highway design (among other applications,) has partnered with the Open Design Alliance to provide users and software developers with high-performance libraries supporting read/write access to their native MicroStation data file format. There are no catches and no games being played here - Bentley's support for open design data formats is in the open, and is real. Users who create designs with MicroStation can be assured that they will control their design data.