Packages.

A package is a packaged unit identified for tracking. Aggregation events record what was packed into what; the gateway stamps the warrantor and the record time itself, grades the asserted observer, and appends the association.

epcListquantityList

Packed in, packed out — as events.

AggregationEvent  action: "ADD"
  parentID:  https://id.gs1.org/00/109520123456788120
  childEPCs: 48 sgtins

AggregationEvent  action: "DELETE"   // three weeks later, at the DC
  parentID:  the same case
  childEPCs: 12 sgtins               // the split, recorded, not edited

Illustrative: an ADD and its later DELETE. Both are appended; the association's history is the pair of events, not a current-state row that was overwritten.

For the engineer modelling pack-out.

The mistake that costs later is treating containment as state. EPCIS treats it as history: what went in, what came out, when, at which step — each an event that validated at the door and cannot be un-written afterward.

Proof, not adjectives. The gateway's conformance tests pass against GS1's normative artifacts. See What for the dimension, and What ships today for the dated ledger.

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