- The first value (number) designates the official concept version. When a new conceptual model is accepted by the OSV team, it will be granted an incremented concept number.
- The second value (letter) designates a variation of that concept. These tend to be significant deviations of the concept, but still generally regarded as derivative.
- The third value (letter) designates a minor version change of that model. Any physical change to the model, no matter how trivial, warrants a minor version change.