The Open Design Alliance is a nonprofit organization of over 1,200 members in 50 countries which develops Teigha, a software development platform used to create engineering applications including CAD. The main idea is to make core graphics technology accessible to software developers allowing them to focus on application development.
The ODA is developing Teigha for two main file formats:
Teigha for .dwg files is a development platform available using C++, .NET, and ActiveX that is used with .dwg, and .dxf files and other graphics files (old names: OpenDWG and DWGdirect).
Teigha for .dgn files is a development platform available using C++ that is used with .dgn files and other graphics files (old name: DGNdirect).
Teigha for Architecture is a development platform available using C++ that is used in conjunction with Teigha for .dwg files to additionally support custom architecture objects.
The Alliance was formed in February 1998 as the OpenDWG Alliance.
In 2002, the OpenDWG library was renamed to DWGdirect.
In October 2003 the alliance was renamed to Open Design Alliance.
On 22 November 2006, Autodesk sued the Open Design Alliance alleging that its DWGdirect libraries infringed Autodesk's trademark for the word "Autodesk", by writing the TrustedDWG code (including the word "AutoCAD") into DWG files it created. In April 2007, the suit was dropped, with Autodesk modifying the warning message in AutoCAD 2008 (to make it more benign), and the Open Design Alliance removing support for the TrustedDWG code from its DWGdirect libraries.
In 2008, support was added for .dgn files with DGNdirect.
In April 2010, DWGdirect was renamed to Teigha for .dwg files, OpenDWG was renamed to Teigha Classic and DGNdirect was renamed to Teigha for .dgn files.