TMZ says:

We’ve learned the person who filed the complaint is a psychologist. Dr. Phil has never been licensed to practice in California, and he retired his Texas license in 2006.
The psychologist who filed the complaint also alleges Dr. Phil violated HIPAA laws by “discussing or divulging a patient’s medical condition … with the media,” in reference to a press release issued by Dr. Phil.

Ha, I knew this was coming sooner or later.