Open Design Alliance

Open Design Alliance is a nonprofit organization creating SDKs for engineering applications. ODA offers interoperability tools for .dwg, .dxf, .dgn, Autodesk Revit, Autodesk Navisworks, and .ifc files and a technology stack for visualization, web development, 3D PDF publishing, modeling, and more.
ODA Products and supported file formats.
.dwg Toolset.
Drawings SDK also provides exchange of the following file formats to and from .dwg and .dgn:
Technology Stack.
The ODA Technology Stack incorporates three products: Visualize SDK, Web SDK, and Publish SDK.
Membership.
There are six types of ODA membership:
There is also a free trial period.
Releases.
Open Design Alliance provides three production releases each year: 
Release notes are created for each release that contain information about product enhancements, new features and instructions for migrating from previous SDK versions.
Intermediate releases are also provided each sprint (month).
Annual ODA Conference.
Open Design Alliance holds an ODA conference every year in September. The two-day conference includes presentations from directors and developers and face-to-face meetings for non-members, members, ODA developers, and ODA executives. Anyone who is interested can register and attend the conference.