Bob deVilder has spent decades transforming a ruined farm building into an ornately-decorated home which has been dubbed the Hobbit house.
Bob, 90, was told in a letter to stop all use of the Lord of the Rings designs and features.
He has been ordered to remove the ornate decoration which adorns the house plus any structures or designs relating to a building from any of the films in the Lord of the Rings series.
This includes the rounded front door, stained glass windows and upper window surrounds. He is also ordered to "cease and desist" from locating the house partly within the hillside at the back.
Lawyers for a top legal team have accused Bob of riding on the reputation of the world-renowned franchise. He has been told to take action immediately.
The property had originally belonged to a local storyteller. Over the years, previous residents of the byre had included a cow, a dragon and a pig. Bob, a skilled builder, decided to convert the byre.
Lawyers who represent Middle Earth Enterprises, which has stage, film and merchandising rights to The Hobbit and The Lord of the Rings, contacted Bob deVilder.
Bob has never seen the films based on JRR Tolkien's books. He told our reporter this was "just a coincidence".