For a rejection based on 35 USC 135(b), under what circumstance is it considered proper?

The rejection based on 35 USC 135(b) is proper when there is a determination that an application conflicts with a claim in an existing patent. This section addresses interferences, which occur when two applicants claim the same invention, potentially leading to confusion about who should be awarded the patent. In this specific case, when John’s claims are found to interfere with Jane's unexpired patent, it indicates that John's claims overlap with those that have already been granted to Jane. This overlap is the essence of an interference situation, which 35 USC 135(b) aims to resolve by allowing the Patent Office to examine the conflicting claims and determine the rightful owner of the invention.

The other scenarios do not meet the criteria for a proper rejection under this specific statutory section. For instance, filing an application before a patent issues doesn't inherently create interference grounds since it's possible the new application could contain different claims or inventive concepts. If claims are identical to those in a previously overcome application, they may not necessarily create an interference unless they are also being pursued in an existing patent that is still in force. Finally, failing to file a terminal disclaimer may affect the patent's enforceability but does not constitute a ground for a proper rejection based on interference. Thus, the circumstances under