The road from a patent application to an issued patent can be a long one. It can take many routes, and there is a Patent Examiner waiting for you at every turn. Understanding how an examiner operates makes it easier to navigate the process. At Michael Best, we use tools like Juristat to gain insights into patent examiners and inform our prosecution strategies. This article highlights the ten most difficult patent examiners, but they are just a small number of the thousands of examiners working at the USPTO. Whether making written submissions, conducting interviews, or filing appeals, the examiner is a key component to each stage. No matter which examiner is assigned to your application, working with an experienced and informed prosecutor will help you make better choices and improve your chances of success.