> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-downloads/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-plus/addressbase-plus-known-data-issues.md).

# AddressBase Plus Known Data Issues

This page provides the details of known data issues in the AddressBase Plus product. Once resolved, details of a known data issue will be held on the page until the next release of the product.

## Live known data issues

| Data Issue Name                                                                | Data Issue Description                                                                                                                                                                                                                                                                                                                                                                                               |
| ------------------------------------------------------------------------------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| UPRNs referencing parent UPRNs that do not exist in product.                   | There are 6 881 Unique Property Reference Numbers (UPRNs) which reference a Parent UPRN that cannot be found in the product. This is because the Parent UPRN is either provisional or historic and is not matched to the Royal Mail Postcode Address File (PAF) or Valuation Office Agency (VOA) record, meaning that it is not included in the AddressBase Plus product as per the existing background logic rules. |
| Records with a sao\_start\_no or sao\_text have no Parent UPRN in the product. | There are 364 records with a sao\_start\_no or sao\_text that have no Parent UPRN in the product. This is because the Parent UPRN is a historical record which is included as part of the logic for record inclusion in the AddressBase Plus products.                                                                                                                                                               |

{% hint style="info" %}
To report an issue not currently listed here, please visit the ['Contact us' page on the OS website](https://www.ordnancesurvey.co.uk/contact-us/business-government/use-os-data).
{% endhint %}


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-plus/addressbase-plus-known-data-issues.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.