What is the prior art date for International Applications filed after November 29, 2000?

The correct understanding of the prior art date for International Applications filed after November 29, 2000, is anchored in the specifics of the Patent Cooperation Treaty (PCT) and the relationship it has with U.S. patent law. For International Applications that designate the U.S., the prior art date is indeed the date the International Application was filed. This is established under the PCT rules and has been reinforced through various legal interpretations and practices since the United States became a member of the PCT.

When an International Application is filed, it is treated as a single application that can later enter national phases in member countries, including the U.S. If the application designates the U.S. for protection, the international filing date serves as the prior art date for assessing novelty and non-obviousness under U.S. patent laws. This date is critical because it determines what prior art could be used against the application if it were to be examined later in the U.S.

To clarify, while some might consider the filing date in the U.S. or the payment of fees to impact prior art status, those do not align with how prior art dates are established under international treaty obligations. The idea that the prior art date is irrelevant for International Applications is also