Legal Question in Intellectual Property in California

If you write your own letters he will ignore you. If there is a person in the U.S. importing products infringing your patent, you may sue him for damages and an injunction (a court order) prohibiting him from further acts of infringement. But you will have to retain an attorney and sue him in federal court in order to do this. Watch out for legal time limits.

Assuming you actually have a 'protect-able' patent, and assuming you can prove infringement and monetary damage, then you may issue proper 'cease and desist' notices, followed up by appropriate lawsuit filed timely. If serious about hiring counsel to do so, feel free to contact me.

I think the most critical aspect is to form a somewhat more educated opinion as to whether your infringement claim would stand up in Federal court. You don't need to be sure you'd win, but I would suggest you take an example of the infringing product and a copy of your patent, and an example of an "authentic" product on the market and produced with your permission, if any exist, to a patent attorney in your area, for an initial professional opinion. Such an initial conference should be low-cost, perhaps free. Another aspect you might want to investigate is whether the infringer is able to pay a judgment. A lot of fly-by-night outfits are importing replicas from China and elsewhere, but don't have two nickels to rub together.