Answer: (1) sue them in Federal Court; or (2) File a complaint with the United States International Trade Commission (USITC).
A patent provides the patentee the right to prevent others from (1) making, (2) using, (3) selling, (4) offering for sale, or (5) importing the claimed invention.
Depending on circumstances, it may be more beneficial for a U.S. patentee to file a "337 Complaint" with the USITC.
A patentee should evaluate the different options available.
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