Is this something we can find out without having to use third-party tools? Yes, it is possible to do this from within Facebook itself. You can also change the settings so that certain folks are not allowed to share your posts.
How to see who is sharing your posts on Facebook
If you want to learn how to find out the people on Facebook who are sharing your posts, then:
You should now see a list of people who have shared your post. The final step here is to click on the Share button in order to have a look at additional data regarding who has shared the post. When the Share button is clicked, a small window will appear. This contains a list of all the people who have shared, along with any comment or emoji they might have added. If you want to, you can click on their names to visit their profile.
How to change Who can see your future Facebook posts setting?
Folks who want to limit who can share their Facebook posts will have to make the changes via the Settings area. Let us discuss how to accomplish this. The option is also there to limit who can interact with your past posts. READ: How to create custom Friend list on Facebook
Why can’t people share my Facebook post?
If you’re wondering why people cannot share your Facebook posts, then chances are it has much to do with the Settings. Please check to see if the Settings allow others to share your post and make the relevant changes to ensure that they can.
Can you share someone else’s post?
You are only allowed to share someone’s post from Feed to your story, but only if their account is public and if they’ve made it possible for others to share their posts. Always remember that sharing from Feed to Stories is not available to all users.