Can a product-by-process claim be anticipated by a prior art product made by a different process?
Yes, a product-by-process claim can be anticipated by a prior art product made by a different process. MPEP 2113 clearly states:
“[B]ecause validity is determined based on the requirements of patentability, a patent is invalid if a product made by the process recited in a product-by-process claim is anticipated by or obvious from prior art products, even if those prior art products are made by different processes.”
This means that if the end product of your claimed process is indistinguishable from a prior art product, your claim may be rejected, even if the prior art product was made differently. The focus is on the product itself, not the process of making it.
To learn more:
Topics:
MPEP 2100 - Patentability,
MPEP 2113 - Product - By - Process Claims,
Patent Law,
Patent Procedure