UPDATE 3:30pm 7/28/2015:
Fox has moved up the embargo for Fantastic Four reviews by one day. The embargo now lifts on Wednesday, August 5, at 6:00pm PST as opposed to August 6 at 4:00pm Pacific:
The original story is below:
A sure sign that a movie is garbage is when a studio embargoes reviews of it until the release date, and that’s exactly what Fox is doing with the Fantastic Four reboot.
Online reviews are not allowed to go up until 4:00pm Pacific on August 6th, which just so happens to be right when the first 7:00pm showings will begin on the East Coast. Print reviews (such as Newspapers) are embargoed until August 7th, which is the day of the release. This is not a good sign for the movie that Fox has already scheduled a sequel to.
This is from the Senior Editor at New York Magazine/Vulture:
Review embargoes aren’t uncommon. Even Marvel does it, but they do it to a specific date so they can control the coverage and allow everyone to post their reviews at the same time. They don’t embargo them until the day of release either, they will sometimes embargo them for the Monday prior to release so that entire release week is dominated by news of the movie.
But when a studio embargoes reviews until the movie is actually playing in theaters it’s 99% of the time a sign that the movie is crap. They want to try to get those advance ticket sales locked in before people can find out how bad the movie really is. For comic fans this could be a good sign as if the movie bombs horribly, maybe Fox won’t make that sequel and eventually the rights will revert back to Marvel.