From the SourceForge website:
Description
This is the .NET code used by the Revit 2015-2017 family of products to support IFC, and the Revit 2012-2014 families of products to support IFC export. The open source version can override the version that comes standard with shipped Revit. Revit 2013-2017 contain both IFC export and IFC export UI overrides, which contain options not available in the regular UI, such as ifcXML and ifcZIP support. The Revit 2014-2017 versions also work for Revit LT…
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