Jerry B. Goldman, 59, was arrested in Los Angeles on Wednesday morning (07Nov12) after a federal grand jury indicted him for mail fraud.
Following an FBI investigation, the agent is accused of overbilling four clients, including superstar Hanks and musician Summers, for more than $800,000 (£500,000) between 1998 and 2011.
In an arraignment on Wednesday afternoon, he pleaded not guilty to 10 counts of mail fraud and was released on a $25,000 (£15,625) bond.
The indictment did not include a breakdown of each client's alleged losses, according to the Los Angeles Times.
A trial date has been set for 18 December (12).