The recent decision by the U.S. Court of Appeals for the Federal Circuit (CAFC) in Celanese International Corp. v. International Trade Commission (ITC) affirmed the ITC’s ruling that Celanese’s process patents were invalid due to secret sales of products made using the claimed process before the one-year on-sale bar. This ruling was based on the interpretation of Section 102(a) of the U.S. patent law, which has a long history dating back to the Patent Act of 1836.
The case involved Celanese’s patents covering processes for making artificial sweeteners, which were allegedly infringed by high-potency sweeteners sold by a Chinese chemical manufacturer. It was found that Celanese’s process was in secret use in Europe, resulting in sales of sweeteners in the United States more than a year before the patents’ effective filing date. The Federal Circuit rejected Celanese’s arguments that changes brought by the America Invents Act (AIA) altered the on-sale bar, emphasizing the importance of the long-standing interpretation of the on-sale bar in U.S. patent law.
Celanese argued that changes in the AIA, such as replacing “invention” with “claimed invention” and adding the phrase “otherwise available to the public,” should impact the interpretation of the on-sale bar. However, the Federal Circuit found these changes to be clerical refinements with the same meaning and emphasized that the addition of new phrases in the AIA did not alter the established interpretation of the on-sale bar.
Furthermore, Celanese’s arguments regarding the AIA’s changes to other parts of the patent statute, such as the grace period for public disclosures and infringement statutes, were also rejected by the Federal Circuit. The court emphasized that the on-sale bar pertains to patentability and is distinct from issues of infringement and third-party actions.
In conclusion, the Federal Circuit’s decision reaffirmed the long-standing interpretation of the on-sale bar in U.S. patent law and emphasized that statutory changes brought by the AIA did not alter this interpretation. This case serves as a reminder of the importance of understanding the historical context and judicial interpretation of patent laws when asserting patent rights based on sales of products made using a secret process.