Services.
Not every observation is a physical object: a service or a business transaction can be the subject of a transaction event. EPCIS 2.0 models it with the same envelope, and the gateway applies the same laws. A hosted service catalogue is future tense; the interface that accepts these events is written and runs locally.
epcListquantityList
Build state, 29 July 2026. The capture gateway is written and passing its conformance tests; nothing is hosted yet. See What for the dimension, and What ships today for the dated ledger.