I think that it would be a good idea to add to that data model specification a list of friends with whom the user has shared that route.
The turtle triple could be something that links a WebId of a user with the WebId of the user with whom he wants to share the content:
<https://user.solid.community/profile/card#me> <https://schema.org/sharedContent> <https://otherUser.solid.community/profile/card#me>.