What is the "prior art" date for a 102(f) rejection of a U.S. published application?

The prior art date for a 102(f) rejection of a U.S. published application is indeed the filing date of the application. Under Section 102(f) of the Patent Act, a person shall not be entitled to a patent if he fails to establish that he is the true inventor of the subject matter sought to be patented. In examining this type of rejection, the relevant time frame is tied to the filing date, as it is when the application is officially recognized by the U.S. Patent and Trademark Office (USPTO) as being submitted.

This means that any prior art that is relevant for assessing inventorship and validity would be measured against the filing date of the application. Other dates, such as the date of public use, patent grant, or conception, do not specifically pertain to the 102(f) rejection context or influence the determination of inventorship as outlined in the patent laws. Hence, the filing date serves as the appropriate and critical benchmark for establishing prior art in this case.