If someone infringes your patent, you have several options. Initially, you can send a cease and desist letter to inform the infringer of your patent rights and request that they stop the infringing activity. If this does not resolve the issue, you may negotiate a settlement, which can include licensing agreements or financial compensation. If necessary, you can pursue litigation to enforce your rights and seek damages. A patent prosecution attorney can help assess the situation, recommend the best course of action, and represent you in negotiations or court proceedings, ensuring your intellectual property is protected effectively.