Continuity mistake: The licence plate of the taxi which hits Sebastian in the end changes during the shot.
Continuity mistake: When Sebastian gives Kathryn the magazine so she can read the article, it is folded in the middle. when you see what she is reading, the page is smooth.
Continuity mistake: When Sebastian goes to visit Blaine, Blaine is using a scale to weigh out some marijuana. In one shot, there is a big pile on the scale, the camera cuts away. When the camera comes back to Blaine, there is a much smaller pile of marijuana. The camera cuts away and back again...the big pile has reappeared.