Factual error: In the beginning where Tooth is sending her fairies to various regions, she sends a few to Moscow, stating that there are "22 incisors and 18 premolars" that need collecting. Premolars are not baby teeth; they are permanent adult teeth. (00:06:10)
Factual error: At the start of the war, it says Fort Sumter 1861. However, on the battlefield we see the US flag with 35 stars. In April 1861, there were only 33 states.
Factual error: Detective Sebastian fires a total of 7 rounds at the Antigen van in the parking garage - three at the driver, two at the front-left tire, one right before the van nearly runs him over and then one after it passes him - without reloading, yet the Taurus Judge revolver he is using is designed to only hold 5 rounds in its cylinder. Later, after Sebastian has reloaded the revolver, he fires 8 rounds at Dr. Lane, again without reloading.
Factual error: On the Amtrak train, "Vicki" sees a sign advertising downhill skiing trips to Victoria, BC. There are no downhill ski areas in Victoria, or close by, and Amtrak doesn't travel to Victoria.
Factual error: When Bella is driving back from Seattle, the speed limit signs say 80. There is no 80mph speed limit road between Seattle and Forks; the movie was filmed in Vancouver and the sign is, in fact, in kph. (01:04:55)
Factual error: John Carter, while gold prospecting in 1868, is arrested by members of the 7th Cavalry, with the intention of employing him to fight the Apache in the Arizona and New Mexico Territories. Unfortunately, in 1868, the 7th was otherwise employed in Kansas and Indian Territory forcing the Cheyenne, Kiowa, and Comanche tribes back on their reservations.
Factual error: When Dave shoots Justin 8 times, he empties the magazine of his semi-auto handgun, but he continues pulling the trigger, and the gun clicks several times. Semi-auto handguns do not "click" when they are empty, because it's impossible to pull the trigger. Also, the slide of Dave's handgun does not lock in the open position when the magazine is empty, as it should.