Is the possession based on a true story?

yes the actual plot about it is not there wasn't really a possession like in the trailer but the true event is a man buys an ublic box from a yard sell and one day opens it by mistake thinkng it was something else well when he opened it paranormal stuff happened he was scratched, nightmares, footsteps , ect. They cintinue till he sells it a few years later. the box was gone and the paranormal events quit happening and started happening to the new owner till he sold it in a yard sale, this pattarn repeated till it as eventually sold to a musem