You need to hire an attorney well versed in Cyber issues (you live in NorCal where because of silicon valley, there is no shortage of such talented attorneys). The attorney will likely start by sending this bozo a cease and desist letter, and he/she can advise you of the next best course of action.
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You have come to the right site to find a cyber attorney in your state. Avvo has a terrific "find a lawyer" tool to locate a top-rated Avvo attorney with a low contingency fee.
Attorneys Sargeant and Gansen have given you good advice. You really need to consult a local attorney. Your facts sound pretty complicated and need a thorough review. Try the Find A Lawyer tool on Avvo for starters. Good luck.
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