---
title: "Customize PDF annotation saving permissions in Flutter"
canonical_url: "https://www.nutrient.io/guides/flutter/annotations/save/saving-permissions/"
md_url: "https://www.nutrient.io/guides/flutter/annotations/save/saving-permissions.md"
last_updated: "2026-05-23T00:08:18.091Z"
description: "Nutrient can write annotations into a PDF under the following conditions:."
---

# Customize annotation saving permissions in Flutter

Nutrient can write annotations into a PDF under the following conditions:

- The PDF isn’t password protected. (Note: Some PDFs are protected with an empty password, just to ensure they can’t be modified. Nutrient will auto-unlock them but can’t add annotations to them.)

- The PDF must be in a writable location. Ensure you copy documents to the documents folder to make them writable.

- The PDF must be valid according to the Adobe PDF specification. Some PDFs are broken but still work somewhat, so Nutrient can render the content. If Nutrient detects a mismatch in the object tree or is unable to find objects, annotation saving will be stopped, since there would be a risk of damaging the document.

Nutrient will save changed, created, or deleted annotations to a document on several occasions. Learn more about these triggers in the [auto save](https://www.nutrient.io/guides/flutter/save-a-document.md#auto-save) guide.
---

## Related pages

- [Manually save annotations in Flutter](/guides/flutter/annotations/save/manual-save.md)
- [Embed annotations in a PDF file on Flutter](/guides/flutter/annotations/save/embed-into-pdf.md)
- [Auto save annotations in Flutter](/guides/flutter/annotations/save/auto-save.md)