Part of accepting assignment on your claims to insurance payers will usually direct the insurance payment to your office, rather than being sent to the patient.
There are times when you need to "not" accept assignment. In DrChrono, your options are to accept/not accept per insurance payer. You can set the edit and the system will print your selection in the appropriate spot in box 27 on the HCFA claim form.
Here is a link to an article that will show you how to set the assignment by insurance payer.