In an ANDA case, the district court held that four patents directed to the reformulated version of the pain reliever OxyContin were invalid as being anticipated by or obvious over the prior art.  With respect to the “low-ABUK oxycodone product,” the court held that Eibel Process v. Minnesota & Ontario Paper Co., 261 U.S. 45, 68 (1923), was inapplicable.  Eibel held that “where an inventor discovers a non-obvious source of a problem and then applies a remedy in response, the invention is non-obvious” even if the remedy standing alone was known in the art.  Here, although determining the source of 14-hydroxy in the end product was not obvious, that problem did not need to be solved to arrive at the claimed invention.  Further, the district court correctly disregarded a process limitation, because, in determining the validity of a product-by-process claim, the focus is on the product, not the process of making it.  This is because an old product is not patentable even if made by a new process.  

Purdue Pharma L.P. v. Epic Pharma, LLC, Case Nos. 2014-1294, -1296, -1307, -1311, -1312, -1313, -1314 (February 1, 2016); Opinion by: Prost, joined by Reyna and Stark (by designation); Appealed From: United States District Court for the Southern District of New York, Stein, J.  Read the full opinion here.

Jump to Page