Sandra King & Kyle J. TroutThe availability of personal examiner interviews is an often overlooked tool for gaining valuable protection for your client's inventions while developing an open atmosphere of understanding between the practitioner and the examiner. It can also provide legal benefits to your client during future litigation and clarify the issues in order to avoid limiting language due to misunderstandings of the invention by the examiner.The doctrine of prosecution history estoppel has been well established by the courts as a limitation on the scope of patent claims. The effect of this doctrine, and its ever-evolving case law, on the practice of patent prosecution is well documented in recent case law. Patent practitioners have proposed various novel strategies. Some of these include the filing of additional claims with different permutations of coverage, as well as the preference of cancellation of claims over the practice of claim amendment. In light of the need for limiting prosecution history while retaining the ability to aggressively prosecute claims, the examiner interview becomes an increasingly effective tool for patent prosecution.According to the MPEP, the purpose of the interview is to "develop and clarify specific issues and lead to a mutual understanding between the examiner and the applicant, and thereby advance the prosecution of the application." MPEP § 713.01. During the interview, the practitioner has the opportunity to better explain the invention if the examiner is unfamiliar with the technology, apprise the examiner's general demeanor towards the invention and argue points of merit regarding issues of patentability and reconsideration of rejections. Furthermore, multiple interviews may be conducted before a final rejection if approved by the examiner. The sum of this interaction between the practitioner and the examiner is summarized in a written statement of the "substance" of the interview, entitled the Examiner's Interview Summary.