PPMN_ — Occurrence Aggregation

Occurrences need the ability to aggregate Occurrences sub-Occurrences without having them necessarily be in a sub-chain. This supports the tying together of different types of Occurrences such as a Custody Occurrence and a Pedigree Occurrence. An example is the loading of grain from a farm into a shipping truck that already has grain in it. This is a combination of the grain as well as custody of the grain passing from the farm or depot to the shipping company.