Continuity mistake: During the interrogation scene, a patient asks for a glass of water. When she receives a the glass of water, she lifts her hand to her mouth and makes a drinking motion, but is not holding a glass. A moment later she sets down an empty glass that previously she was not holding. When the camera angle changes, the glass has become half full. She also is "drinking" with her right hand and sets the glass down with her left hand.
Continuity mistake: The morning after Teddy's light-flash migraines, he and Chuck walk out into the center courtyard and look upon the havoc wreaked by the thunderstorm. Teddy glances up at the electric wires around the gated perimeter and sees a branch that had fallen and bent the line. In the first shot, the log is leaning into the courtyard. The shot then cuts closer and the log is leaning outside of the courtyard. When the shot cuts back to Teddy, the log is once again mostly inside the courtyard.
Other mistake: During the flashback of the soldiers executing the Dachau guards, the soldiers are in a line opposite the guards who are in a line against a fence. The soldiers all start shooting at the same time, but we are shown the guards being mown down by gunfire in succession, like dominoes, rather than simultaneously.
Continuity mistake: When Leo has the doctor against the wall near the end with the syringe in his hand, in the angle looking at the doctor, the needle is closer to his neck, but when it switches sides to Leo, he is holding the syringe farther from his neck, within the space of seconds.