Can our Outlook and Microsoft 365 email be licensed to AI companies, and how do we get it out?
Often yes, if the company holds the rights and removes personal and restricted messages first. For a whole organization, mail usually comes out through Microsoft Purview eDiscovery, run by someone with eDiscovery roles; single mailboxes can be exported to PST (Outlook's mailbox archive format) files from Outlook. Some buyers instead connect with read-only access.
What is in company email, and why do buyers want it?
Email is often a company's longest-running record. It holds quotes, negotiations, order problems, vendor coordination, support replies, and internal decisions, often going back many years.
AI companies value business email because it shows how professionals write, explain and resolve issues over time. Threads with a clear beginning and outcome, such as a customer issue raised and then solved, tend to be most useful.
Usually in scope
- Work conversations about operations
- Tickets, tasks and project histories
- Process documents and SOPs
- Orders, invoices and workflow records, de-identified
- Code repositories you own outright
Commonly left out
- HR, payroll and personnel files
- Board, legal and M&A material
- Direct messages and private channels
- Data you hold for customers under contract
- Health, financial-account or other regulated personal data
How does an organization-wide export work?
As of October 2026, Microsoft documents eDiscovery in Microsoft Purview as the way to search and export mailbox content across a tenant. Results from Exchange mailboxes export as PST files or individual messages, with primary and archive mailboxes combined into one PST per mailbox.
Microsoft notes some practical limits:
- The exporting user needs the Export and Preview roles, which come with the eDiscovery Manager role group.
- That user needs a Microsoft 365 E3 or E5 license.
- Export packages are deleted 14 days after creation, and exports that run more than seven days are cancelled, so large jobs should be split by date range.
What about a single mailbox or older Outlook archives?
Microsoft's support page explains how to export email, contacts and calendar items to a PST file from Outlook. This suits a small business or a single archived mailbox. Microsoft notes that the new Outlook for Windows does not yet support calendar or contact items in PST files.
If the company still has old PST archives on file servers or laptops, those are also email records. Gather and inventory them centrally; do not let individuals send them out.
Does it have to be exported?
Some buyer programs read mail through an app registered in your Microsoft 365 tenant instead of taking PST files. An administrator has to approve its mail-read permission, and by default that can cover every mailbox. Ask whether access can be limited to selected mailboxes, where copies are stored, and how they are deleted when the license ends.
What should stay out?
- Mailboxes of HR, legal counsel, payroll, and executives, unless separately reviewed.
- Privileged communications with lawyers.
- Personal messages and messages about employees' health, family or performance.
- Customer personal data, payment details, and attachments with ID numbers.
- Threads covered by NDAs (nondisclosure agreements) or customer contracts that bar reuse.
What rights questions should you check?
Microsoft's terms generally let you export your own tenant data, but email always includes messages written by people outside the company. Customers, vendors and partners may have contract or privacy rights in what they sent. Employee privacy laws such as the CCPA (California Consumer Privacy Act) can also apply. Read our guide on employee and customer privacy and talk to your lawyer.
Where should you start with email data?
Check your Microsoft 365 licensing first, since Purview export needs an E3 or E5 license on the exporting account, and decide which mailboxes are out from the start (legal, HR, executives). Also round up stray PST archives on old laptops and file servers. Plan exports in date-range batches so none run past Microsoft's seven-day limit.
Common questions
Do we need an E5 license to export?
Microsoft's Purview export page says the eDiscovery user needs a Microsoft 365 E3 or E5 license. Check your current licensing with your IT provider.
Can we use old PST files?
Yes, PST files are mailbox exports. Collect them centrally, inventory what they contain, and screen them like any other mail.
How do we keep attorney emails out?
Most exports can be filtered by mailbox, sender, recipient, and date. Exclude legal counsel addresses and review anything marked privileged.
How big are export files?
Microsoft lets you choose PST package sizes from 1 GB to 10 GB, with 5 GB as the default.
Sources
- Export search results in eDiscovery | Microsoft Learn, accessed 2026-10-15
- Assign permissions in eDiscovery | Microsoft Learn, accessed 2026-10-15
- Export emails, contacts, and calendar items to Outlook using a .pst file | Microsoft Support, accessed 2026-10-15
General information, not legal, tax or financial advice.