---
title: "OCEL (Object-Centric Event Log) 2.0 Specification"
type: source
tags: [ocel, event-log, standard, process-mining, object-centric]
authors: [Berti Alessandro; Koren István; Adams Jan Niklas; Park Gyunam; Knopp Benedikt; Graves Nina; Rafiei Majid; Liß Lukas; Tacke Genannt Unterberg Leah; Zhang Yisong; Schwanen Christopher; Pegoraro Marco; van der Aalst Wil M. P.]
year: 2023
venue: "OCEL Standard Document, RWTH Aachen (ocel-standard.org), 16 Oct 2023"
kind: specification
raw_path: "raw/Predictive process monitoring/ocel20_specification.pdf"
created: 2026-04-13
updated: 2026-04-13
key_claims:
  - OCEL 2.0 is a more expressive and simpler standard than XES for object-centric process mining (OCPM).
  - Can depict object changes, object relationships, and qualified relationships.
  - Three exchange formats — relational SQLite, XML, JSON.
---

# OCEL 2.0 Specification (RWTH Aachen, 2023)

Technical specification document for the **Object-Centric Event Log (OCEL) 2.0** standard. Led by [[entities/wil-van-der-aalst]]'s Chair of Process and Data Science at RWTH Aachen.

## Why it matters for PPM
OCEL formalises the **object-centric** data representation that Object-Centric Process Mining (OCPM) operates over. Most PPM literature to date uses XES (case-centric), but the object-centric view is richer — cases can share objects, and prediction can be formulated per-object rather than per-case. Emerging [[concepts/predictive-process-monitoring|PPM]] work is beginning to adopt OCEL (cited in [[sources/2026-calvanese-agentic-bpm-manifesto]] indirectly via process-mining references).

## Structure
- Metamodel of events, objects, event-to-object (E2O) relationships, object-to-object (O2O) relationships, with qualifiers.
- Three exchange formats: relational (SQLite), XML, JSON — each with a validation schema.

## Connections
**Concepts:** [[methods/process-mining-basics]] · [[concepts/predictive-process-monitoring]]
**Authors:** [[entities/wil-van-der-aalst]]