Continuity mistake: When Russell Crowe walks towards Ben's diner in the outside shot, he has his bag over his shoulder, and it is stolen from the ground under his spot at the counter a moment later. When he enters the diner (the inside shot) he doesn't have his bag. So he couldn't have put it on the ground, and it couldn't have been stolen from there. (00:29:00)
Continuity mistake: Crowe gives the girl reporter a necklace made of ballpoint pens. When Crowe leaves and she runs after him the necklace is gone. (01:47:45 - 01:48:45)
Answer: The assassin that Stephen hired to spy on Sonia found out and told Stephen. At some point off-screen, Stephen told Anne details about his affair with Sonia and accidentally told her that she was being paid to spy on and sleep with him for $26,000. Anne told Cal about the $26,000, and Cal realises that Stephen knows a lot more about Sonia's spying for Point Corp than he is letting on. If Stephen was completely innocent, there would be no way for him to know the amount was $26,000. Cal and his team of journalists never told Stephen the specific amount of money Sonia was getting.