Hi Molly. Thanks for asking.
If you are part of the paid program on Medium, your readers will be able to read one or two stories for free in a month. They have to pay after that to see the whole story.
So if I share on social media, I always make sure I copy a friends-link. You find the friends-link when you click on the little wheel at the top of your story on the right. Copy the friends-link and they will always see the whole story when your readers click on your link.
It’s only possible for the writer to share a friends-link, so I cannot do it when I share a story form another writer.
Hope it answers your question. If not, don’t hesitate to ask again.
Warm regards, Desiree.