Hello Steve,
I can't say because I have an account and I have been invited to view trees.
But this does answer it: :biggrin:
Trees are shared by providing others a link to your online tree ... In order for your friends or family members to view your tree, they must already have an A.... account, whether it be a paid membership or a registered guest account. If they do not have an account, they can sign up for a free registered guest account. The invitation you create and send will provide a link to the sign up page. All that's required is their first name, last name, and an email address.