What determination made by the Director is considered final and nonappealable?

The determination that is considered final and nonappealable is the finding that no substantial new question of patentability was raised. This determination occurs during the examination process and is related to the review of applications and prior art. When the Director concludes that there isn't a substantial new question regarding whether the claims of a patent application are novel or non-obvious compared to existing knowledge, that decision stands as final.

Such findings are critical because they help streamline the patent examination process by indicating that the claims do not warrant further review or pursuit. As a result, this determination is not subject to appeal because it is deemed conclusive regarding the specific issue of patentability at that stage of the examination.

In contrast, other options involve determinations that are either procedural or involve operational aspects of the patent review process, which may be subject to further review or appeal. For instance, granting extensions or reviewing requests for application review can be challenged or reconsidered, while judgments on interferences may involve a different mechanism of dispute resolution that is also subject to appeal.