Tauri Migration

Mergers, acquisitions, divestitures: combine or split Microsoft 365 tenants

An acquisition plays out over months: teams must work together before everything has moved. Documents migrate in waves, at the teams’ pace.

Short answer

Tauri Migration handles the document side of a merger: SharePoint sites, OneDrive and file shares, in waves, with incremental re-runs. Accounts, mailboxes and Teams belong to other tools, run beforehand.

Three set-ups

Absorption

The acquired company’s tenant joins the group’s. Its sites become group sites and its users change domain.

Divestiture

A business that is sold leaves with its documents for a new tenant. Only its sites and folders are copied; nothing else moves.

Consolidating subsidiaries

Several tenants converge into one. Each subsidiary is a project, with its own connections, waves and reports.

Order of work

  1. IdentitiesAccounts and groups exist in the target tenant (sync, creation, invitation). This is what lets authors and permissions be translated.
  2. Mail and TeamsWith the dedicated tools, from Microsoft or third parties. Tauri Migration migrates neither mailboxes nor teams.
  3. Documents, in wavesOne action per wave: department by department, or site by site. Each wave has its own state database and reports.
  4. Incremental passesWhile the two companies coexist, re-run the waves already migrated to carry over new content.
  5. CutoverWave by wave, the source goes read-only and a last pass runs.

What helps in this context

  • Domain rules translate every account of the acquired company in one line, guests included.
  • Excel template so business owners can approve the waves before import.
  • Missing accounts replaced by a fallback account in metadata only: permissions are never handed to someone else.

Frequently asked questions

Can we start before every account has been migrated?

Yes for sites whose accounts all exist already. A missing account is replaced by the fallback account in metadata and reported; its permissions are not applied.

Can both companies share documents during the transition?

Yes: while the source stays active, each incremental pass carries over what changed there. Changes made in the target do not flow back to the source.

Test it on your own tenant

The 14-day trial migrates 10% of every library, with versions, metadata and permissions. After you subscribe, an incremental run migrates the rest.

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