In my June 22, 2009 post, I discussed the district court decision that found a claim to optically-pure oxaliplatin (U.S. Pat. No 5,338,874) not infringed by defendants who made it by processes other than the HPLC process disclosed in the specification. I noted that this was an extreme case of “patent profanity” being used against a patentee to effectively convert a compound claim into a product-by-process claim, despite qualifying language used in the specification that HPLC purification is an “illustrative method” and a “representative process” by which the claimed compound may be prepared. I suggested that such language should always be employed and that applicants should focus on the distinguishing properties of the claimed compound when arguing patentability, not on the need to use a specific process to prepare it.
These are just the arguments that Sanofi used on appeal (Please see disposition attached at the bottom of this post), and the Federal Circuit found them convincing.:
“[H]ere the patent specification and prosecution history focus on the property of the composition (optical purity) and not the process used to obtain that property. The specification defines the invention as oxaliplatin of optically high purity, not oxaliplatin prepared by the disclosed HPLC process. … The specification never asserts that HPLC is required to obtain optically pure oxaliplatin … the prosecution history also illustrates that it is the optical purity of oxaliplatin that distinguished it from the prior art, not the process used to obtain that purity.”
Nonetheless, as noted in my prior post, the district court did locate enough references of the need to use a “specific” process to obtain the optically-pure material, to justify reading the HPLC process limitation into the claim. While the Federal Circuit barely references the defendants’ arguments, the court distinguished the primary decision relied upon by the district court, Andersen Corp. v Fiber Composites, LLC, 474 F.3d 1361 (Fed. Cir. 2007). In that case, a processing limitation was added to a structural claim, “where that patentee relied on that process both to define the invention and to distinguish the prior art.” The Federal Circuit “determined that the specification attributed the claimed physical properties to the process and that the specification indicated that the pelletizing step was a requirement, not a preference, of the invention …[and] that the patentee had clearly disavowed other processes during prosecution.”
I don’t think that this decision provides the “last word” on what constitutes clear disavowal of “other processes”, but it is clear that drafters should always use lots of qualifying language, even if only one method is disclosed to yield the claimed product. Also, the novel and unobvious properties of the resultant product should be the only focus of patentability arguments, and not how clever applicants were to figure out the process that finally yielded it, let alone that the process is essential to the novel and unobvious properties, e.g., that it imparts them in some way. Also, other processes that could conceivably yield the claimed product should not be disparaged, even if they are in the prior art. Can you reliably protect your compound claims (much less your process claims) from this sort of attack? Probably not, but don’t expect generic oxaliplatin on the market any time soon.