> For the complete documentation index, see [llms.txt](https://city-protocol.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://city-protocol.gitbook.io/docs/tokenization-as-a-service/tokenization-architecture/oracle-and-verification-workflow.md).

# Oracle and verification workflow

The oracle and verification workflow is designed to protect users from stale, incorrect, or manipulated product values.

If a NAV update falls outside predefined deviation limits, fails verification, lacks required signer approval, or uses incomplete data, the product can pause new subscriptions, redemptions, or both until the issue is resolved.

<figure><img src="/files/zFzmKpHcysb64NmifZOz" alt=""><figcaption></figcaption></figure>

```
    A["Strategy / Asset Data"] --> B["Data Validation"]
    C["Reserve / Custody Data"] --> B
    D["Service Provider Reports"] --> B
    B --> E["NAV Calculation"]
    E --> F["Deviation Check"]
    F --> G{"Within Policy?"}
    G -- "Yes" --> H["Co-signer / Oracle Quorum"]
    H --> I["Publish NAV Onchain"]
    I --> J["Subscriptions, Redemptions, Reporting"]
    G -- "No" --> K["Pause / Review / Manual Resolution"]
```