According to a post on Reddit, Disney sent an email to theaters warning them against doing an advance employee screening for Star Wars: The Force Awakens. Any theaters that shows the movie before the first public screenings on December 17th will have the movie pulled entirely from their theaters. Considering that Star Wars: The Force Awakens will likely make up a large portion of December revenue for most theaters, the threat of pulling the movie is quite a big one from Disney.
According to subsequent posts on Reddit, theater executives are allowed to a quality check viewing of the film on Wednesday, but employee screenings are strictly off limits. There is a world premiere screening being conducted on Monday and limited press only screenings happening on Tuesday, but outside those few screenings, it looks like everyone else will be seeing the movie at the earliest on Thursday night.
Star Wars: The Force Awakens opens in wide release on Friday, December 18, 2015.