Sharing a report within same domain

Hi all,

I've downloaded PowerBI desktop and I've logged in using my Company Office365 account (myemail@companyname.com). This is a basic PowerBI account, not Pro.

I've created a report and I'd like to share it with other colleagues in the same domain only (companyname.com). Even with everyone in my company domain would be ok, but not externals.

I've tried to use the share report feature but I get a URL link that I can still view from any account. 

(https://powerbi.microsoft.com/en-us/documentation/powerbi-service-share-unshare-dashboard/)

Do I miss something? Or it is simply not possible to do this with the standard PowerBI account?

Thank you!

Giuseppe