Sharing a notebook: what others can then open

What happens when you share

Microsoft's support page puts it plainly: "Sharing a notebook doesn't just share the notebook, it can also give others access to files inside it." When you invite someone, they're automatically invited to all the linked files, so Copilot can answer their questions right away.

There are limits. You need sharing permission on each linked file. Where you don't have it, the other person has to request access. Some files may stay restricted if permissions can't be passed on automatically. And Microsoft's admin documentation adds that chats in a shared notebook are private: each person has their own conversations with it.

Premium sources, which Microsoft lists as Teams content, SharePoint and OneDrive content and internal URLs, only work for people with a Microsoft Copilot licence. A Copilot Chat user can open a shared notebook but may not get answers from those sources.

Why this matters for decisions

A notebook built for a decision often contains material that was gathered for one audience: draft figures, a frank meeting note, a supplier's commercial terms. Sharing it with a wider group to "keep everyone informed" may also share all of that.

The opposite mistake is possible too. If you share a notebook with someone who can't get access to half the references, their answers from Copilot will be based on a different set of evidence from yours. Two people asking the same notebook the same question could get different answers, and neither might notice.

A check before you share

I'd do four things.

1. Read the reference list as if you were the person receiving it. Remove anything they shouldn't see.
2. Look for whole folders or sites. Adding a SharePoint folder as a reference can bring in many files, and sharing the notebook may invite people to them.
3. Check whether the recipient has a Copilot licence if the notebook relies on SharePoint, OneDrive or Teams content.
4. Tell them what the notebook is for, and which question it was built to answer.

A worked example

This scenario is illustrative. A project lead's notebook for a vendor decision has eight references: two proposals, a scoring spreadsheet, the procurement policy, three meeting recaps and an HR note about a contractor's notice period. She wants to share it with the wider project team.

The HR note was added to answer a scheduling question and shouldn't go any further. She removes it first, then shares. One team member, who has Copilot Chat only, finds the meeting recaps aren't used in his answers. So she puts the key points from the recaps into a Copilot Page in the notebook, which Microsoft lists as a standard source, and the gap closes.

What administrators should know

Notebooks live in a user-owned SharePoint Embedded container, which shows in admin tools with the application name "Loop". Microsoft's compliance summary says Information Barriers aren't supported for this content. Organisations that rely on Information Barriers may want to use the admin policy that controls creation of Copilot Pages and Notebooks until that changes.

What I'm still checking

I'm not sure how sharing works when the notebook owner later adds a new reference. My reading is that sharing is evaluated per linked file, but I haven't found Microsoft guidance on whether new references are automatically shared with existing members. I'd test it before relying on either behaviour.

Sources

• Microsoft Support, How to share a Microsoft Copilot Notebook, accessed 11 October 2026.
• Microsoft Learn, Overview of Copilot Pages and Copilot Notebooks permissions, accessed 11 October 2026.
• Microsoft Learn, Summary of governance, lifecycle, and compliance capabilities for Copilot Pages and Copilot Notebooks, accessed 11 October 2026.
• Microsoft Learn, Admin policies for Copilot Pages and Copilot Notebooks, accessed 11 October 2026.