Facebook is reportedly testing out a new option which would enable users to share their Facebook and Messenger Stories with smaller, selected groups of friends, as opposed to all of their connections.
As you can see in this example, shared by reverse engineering expert Jane Manchun Wong, the option would provide a new 'Favorites' list option for you to share your Stories to. Tap on the Favorites listing and you would be able to select users to include on the list.
That seems to align more with the broader usage of Stories as a more private option - the format originated from Snapchat, where communication with your closest connections is the focus.
From a brand perspective, the option could also provide a way to share with selected users, and help to build engagement with key advocates.
Back in June, Facebook added a similar option with 'Top Fans' as a targeting tool for Facebook Page posts.
You could look to use this function in the same way, providing exclusive Stories content for chosen members of your community, adding a level of exclusivity which could help to foster brand loyalty.
There's no word on any official release, or how the functionality would work (for example, could those on that initial 'Favorites' list then re-share the story from their profiles?), but it could be another element to watch in 2020 as a potential addition to your Stories strategy.