Corrected entry: In Chapter 10, Fingers and Thumbs, Spiro tells Artemis that his cousin Costa had surgery so that he could take his place. Spiro had set the gel scanner to accept Costa's fingerprint for one night only. Later in the chapter Artemis claims to have reverted the cube from version 1.2 to 1.0. After Spiro tests the cube he claims "I have no family, no heirs." This statement contradicts what he had said about his cousin. He could not possibly have a cousin and no family.
Corrected entry: Towards the very end of the book, during the mind wipe, Foaly mentions that he is able [through technology] to read the humans' minds like "a book. Even though Artemis was able to evade the mesmer through usage of mirrored contact lenses, his memories of designing the lenses, as well as those of scheming, plotting, etc., would have been easily accessible to the intelligent and technologically armed-to-the-teeth centaur. However, Foaly conveniently fails to notice ANY memories of Artemis' plots - including the information on the laser disc, giving orders to Butler to plant false trails, and even more incriminating memories.
Correction: The book implies that it wasn't Foaly himself 'reading the memories like a book,' but a computer program designed by Foaly to do it for him. Was Foaly going to sit through year's worth of memories and delete them one by one? No, but his program would.
Corrected entry: In chapter 8, when Jon Spiro opens the door to the vault, the book states that four things had happened, but if you count carefully, only three things had happened.
Correction: Foreshadowing - the fourth thing is the weight-checking device that Artemis finds out about accidentally at the climax.
Correction: Spiro means that he doesn't have any family that he actually cares about; no sons or daughters for whom he would want to preserve the world, merely a cousin he manipulates. The point is, he has no one that matters enough to him that would stop him from destroying the world.