Can my law practice operate as a dba of my California sub s corp?

Yes. Make sure you notify your malpractice carrier of any changes you make. Good luck.

I agree with attorney Doland and you may also check with SBC to make sure if there any updating or reporting requirement regarding the dba of the corporation which would be engaged in the practice of law, I think it needs to be a professional corp. whether "s" or not. Good luck.

You can only operate a law practice as a professional corporation (which can be taxed as a C or S corporation), a flexible purpose corporation, a public benefit corporation or a nonprofit corporation. As far as the fictitious business name, you will need to register the corporation with the State Bar if you use a name that is something other than your actual name.