Factual error: A minor only has a certain amount of time (typically, 6 months) to invalidate a contract entered into when such person was underage once that person turns 18 (or the age of emancipation in that state). This brings up a plot hole: If the marriage was not invalidated because Samantha Cole was underage, the prenuptial agreement would not be either, and Fletcher could not have used that argument to win the case, since he specifically states that she was seventeen at the time of her marriage.
Continuity mistake: In the scene where Fletcher is in his office and he's trying to write that the pen isn't blue, he swipes everything from his desk and there's then an overhead shot showing the only thing left on his desk is a small piece of white paper on the right hand side. A few seconds later the piece of paper has disappeared and has instead been replaced by what looks like a drinking straw.
Other mistake: When Fletcher is attempting to force himself to write the word "red" on his desk, in the shot before the "blue" is revealed, his pen is not even touching the desk and his final pen movement is a curve which doesn't correspond to an exclamation point.
Continuity mistake: When Fletcher moves underneath the wing of the plane on his flight of stairs, another plane is seen in front of him. It disappears when the pilot sees the shoe land on the windscreen. There is also no sign of the barrier and luggage area that he crashes into a few seconds later. (01:14:50)
Continuity mistake: Towards the end, Fletcher is on the stretcher talking to Max, and looks at his watch to discover he has been able to lie for half an hour. Max then responds "So you lied?". Fletcher then grabs Max's shoulder with his left hand, saying "No! It was the truth!". As the angle changes he is still speaking, but his left hand is now lying across his chest before he reaches out to grab Max again.
Continuity mistake: Just after Fletcher steals the yellow airfreshener from the car yard, he has his arms by his side. When the shot switches back to him, he has his arm on the counter. Considering that he was watching his car in such a shocked state, it's incredibly unlikely he would change to this position. (00:34:40)
Revealing mistake: In the scene where Fletcher drives out of the parking garage almost causing a car accident, you can tell it's his stunt double, because his stunt double is wearing sunglasses and doesn't look too much like Jim Carrey. Then it shows a back view of Fletcher speeding away and his sunglasses are gone.