Undoubtedly, the doctrine of inequitable conduct is one of the key concepts in patent infringement case law in the United States, playing a significant role in judicial decision-making. This doctrine grants courts the authority to render an entire patent unenforceable if it is proven that the patentee deliberately withheld or misrepresented material information before the Patent Office. However, such a legal mechanism does not explicitly exist in Iranian law. Given the doctrine’s crucial role in balancing the rights of Patent Holders and economic actors while fostering a fair legal environment, this article aims to provide a legal analysis of this doctrine within U.S. case law and explore its potential application for developing Iran’s legal framework in the field of patents. The main research question is: How does the U.S. legal system apply the doctrine of inequitable conduct in patent infringement case law, and how can it be utilized to enhance judicial decisions in Iran? Based on the findings of this study, which adopts a descriptive and analytical approach, U.S. judicial practice in applying this doctrine has been inconsistent, oscillating between excessive strictness and a more flexible approach, leading to divergences among courts. In the Iranian legal system, courts lack an independent mechanism similar to the doctrine of inequitable conduct to assess the bad faith of patentees. Therefore, the Iranian legislature can enhance the accuracy and fairness of judicial decisions in patent litigation by formulating clear and compatible legal provisions tailored to the country’s legal framework.