When Ed is taking his tie off after the meeting with the PG&E clerk, he loosens it, then they cut to Erin, then back to Ed, and his tie is back to tight around his neck, and he's taking something out of his breast pocket. Then they cut back, and his tie is off.
In the diner when you see the real Erin Brockovich (the waitress), you can also see the real Ed Masry. He is sitting directly behind Julia Roberts and her baby. Another side note, look at the real Erin Brockovich's name-badge, it says Julia.