Model View Definitions (MVD)

An IFC View Definition, or Model View Definition, MVD, defines a subset of the IFC schema, that is needed to satisfy one or many Exchange Requirements of the AEC industry. The method used and propagated by buildingSMART to define such Exchange Requirements is the Information Delivery Manual, IDM (also ISO/DIS 29481).
An IFC Model View Definition defines a legal subset of the IFC Schema (being complete) and provides implementation guidance (or implementation agreements) for all IFC concepts (classes, attributes, relationships, property sets, quantity definitions, etc.) used within this subset. It thereby represents the software requirement specification for the implementation of an IFC interface to satisfy the exchange requirements.
Whereas the general exchange requirement is independent of a particular IFC release, the realization (or binding) within the model view definition is specific to an IFC release.
Model View Definitions are either defined within buildingSMART International, or by other organizations and interest group. MVD's defined externally are not considered as buildingSMART MVD's until they are submitted to buildingSMART International, reviewed by the buildingSMART teams and finally accepted.

You can find more information on other bSI pages:

IDM-MVD: How do they provide solutions to user requirements?

Internationalization of Model View Definitions (MVDs)