According to 35 U.S.C. § 102(d), what is considered to be effective prior art?

The correct answer highlights that effective prior art, as defined under 35 U.S.C. § 102(d), pertains specifically to patents and applications that have been filed under certain conditions. This means that if a patent or application has been filed and meets the requirements specified in this section, it can be used as prior art against a later-filed application. This provision ensures that inventions which have been made publicly available through patents or patent applications can be cited to prevent unnecessary duplication of ideas and inventions, thereby promoting innovation while protecting the rights of inventors.

In contrast, the other options do not encompass the detailed legal framework set forth in § 102(d). For example, the notion of considering only applications filed after a certain date fails to recognize the broader scope of what constitutes effective prior art. Similarly, stating that all patents are effective irrespective of their filing dates overlooks the criteria specified for them to qualify as prior art. The idea that inventions disclosed solely by the inventor are the only considerations also misrepresents the range of prior art available, which includes a variety of documents and filings that can impact patentability.