My customer has a holding, let's say "Contoso Holding". Within this Holding, there are 5 companies (So legally there is a sepperation in companies, but there is one group of 8 employees that work for it):
- Contoso Product X
- Contoso Services Y
- Contoso .... Z
Of course you want to keep files and information saved with the right company, so when a company is sold everything that is associated with it is easily handed over to the new owner.
How do I map this to an Office 365 subscription?
Off course I can create 5 seperate subscriptions, with their own single tenant. But there are users that need to access all tenants. Do they need a license in every tenant? So Management Assistant A switches between 5 user accounts and pays for 5 licenses?
Or can I create multiple tenants within one subscription?
Normaly the companies have only one Tenant per group of companies, it depends the holdings of the capital of their percentage of owning that company.
You can separate per company/tenant, but if you have users that work on several companies, if they use for example Editing documents on Sharepoint they do not need licence, just share to other person like an external editor. But if they use email, they need to have a login/licence on the tenant.
It always a decision based on costs/managing, etc.
I had cases that start in separate Tenants and they have migrated to only one tenant. If the company has been sold you have to migrate the data to a new/separate Tenant of that persons per company.