There are cases where you have a group company and you have many companies in your group. Each of the companies might have their own Office 365 Subscription. This presentation explains this scenario and also provides steps to enable and configure in a way that group company users can login with their own AD / O365 credentials and collaborate with the group company's O365 - SharePoint Online Portal. The same approach can also work when you want to share some content with your customers or partners who have their own O365 tenants.

1. Sharing Site between 2
different O365 tenants
Using External Sharing Option
Prepared by Karthick S, SharePoint Consultant & Architect
https://www.linkedin.com/profile/view?id=4795001
05-Apr-15

2. Scenario
• I have two different O365 tenants
• One which is igridconsultingsol.onmicrosoft.com (Tenant 1)
• Another which is demosp2k13.onmicrosoft.com (Tenant 2)
• I have an HR Site in Tenant 1 that I want to share with a user in Tenant
2
• Using External Sharing option, I shared this with a user in Tenant 2
• Then the user in Tenant 2 is able to login through his own credentials
to come into the site (instead of requiring a separate username on
Tenant 1 or even a requirement of a passport account)
• Screenshots and the flow is in this presentation

3. Tenant 1’s HR Site

4. Ensuring External Sharing is enabled (by
default it is disabled)

5. Clicked on Share and entered the e-mail id of
another tenant

6. E-mail invitation received

7. The User clicks on “HR” from the Go to HR
text and gets 2 options to sign in

8. I click on Organizational account
• Then since I am logged in already into my own O365 tenant, it
instantly logs me in – such that I don’t have to sign in again!
• Now I am able to see the HR Site that is shared with me

9. To just confirm that, it has indeed logged me in
through my own O365 tenant, I went to “My
Settings” and it clearly shows me, my own
Organization account & e-mail id only