# Deduplication Key

> A stable identifier attached to a message that lets a consumer detect and drop duplicates.

Record: `lexicon:deduplication-key`
Kind: artifact
Layer: [Execution Core](https://banes-lab.com/records/layer/execution-core.md)
Canonical: https://banes-lab.com/ontology/lexicon#lexicon-deduplication-key

Listed in [Lexicon terms](https://banes-lab.com/api/records/lexicon.md), after [Consumer](https://banes-lab.com/records/lexicon/consumer.md) and before [Event Contract](https://banes-lab.com/records/lexicon/event-contract.md).

## Category

- [Event Messaging Async](https://banes-lab.com/records/lexicon-category/event-messaging-async.md)

## Required by

- [Idempotent Consumer](https://banes-lab.com/records/architecture/idempotent-consumer.md)

## Linked from

- [Event / Messaging / Asynchronous Architecture](https://banes-lab.com/ontology/principles/architecture-category-event-messaging-asynchronous-architecture.md)