SharePoint Online improves external sharing
As written by Mark Kashman on blogs.office.com
Getting work done often requires working not only within the company boundaries but also working beyond the firewall with business contacts who do not fall within your corporate domain. We’ve been hard at work to enhance the external sharing user experience so that sharing is more and more friction free, for both users and admins.
As such, we’ve made the following improvements to SharePoint Online and Office 365:
Get a link: create anonymous Guest Links in one click within
the Office 365 user interface.
Members can share: enable site members to invite external users, not
just the site collection owner.
All invitees on same
email To line: start a collaborative email with *everyone* when sharing a site or document.