The Federal Circuit has issued a precedential decision concerning the written description requirement that is sure to garner much attention. In Novartis Pharmaceuticals Corp. v. Accord Healthcare, Inc. et al. (2021-1070), the Court rejected the imposition of a heightened written description standard for negative claim limitations. The Court explained that as with all other limitations, a negative limitation must be accompanied by an original disclosure which conveys to a person of ordinary skill that the inventor was in possession of the claimed invention. In this instance, the Court upheld the district court's decision that the lack of any discussion of “loading dose” provided written description support for the negative limitation: “absent an immediately preceding loading dose regimen.”
The accused infringer (“HEC”) appealed from a district court bench trial in which the district court found that HEC infringed the patent. On appeal, HEC argued that the district court erred in finding that the claims satisfied the written description requirement of 35 U.S.C. § 112(a). Claim 1 of the patent in suit (USP 9,187,405) reads as follows:
1. A method for reducing or preventing or alleviating relapses in Relapsing-Remitting multiple sclerosis in a subject in need thereof, comprising orally administering to said subject 2-amino-2-[2-(4-octylphenyl)ethyl]propane-1,3-diol, in free form or in a pharmaceutically acceptable salt form, at a daily dosage of 0.5 mg, absent an immediately preceding loading dose regimen.
HEC challenged the district court's decisions concerning the patent's written description of two limitations: (a) the 0.5 mg daily dose limitation and (b) the no-loading-dose negative limitation.
HEC's argument regarding the 0.5 mg daily dose limitation was untenable as a matter of well-established law. The patent specification expressly includes a prophetic human clinical trial in which patients would receive “0.5, 1.25, or 2.5 mg” of an S1P receptor modulator. The Federal Circuit found no clear error in the district court's holding that the 0.5 mg/day dosage limitation is adequately described.
With respect to the written description for the negative limitation—“absent an immediately preceding loading dose” limitation—HEC argued that there is no written description of the negative limitation because the patent specification contains no recitation of a loading dose “or its potential benefits or disadvantages at all.” The Federal Circuit observed that in asserting that “silence alone cannot serve as a basis for” a negative limitation, HEC was attempting to create a new heightened written description standard for negative limitations. In doing so, however, HEC ignored a central tenet of written description jurisprudence—that the disclosure must be read from the perspective of a person of skill in the art—as well as long-standing precedent stating that the disclosure need not describe a limitation in haec verba. The Federal Circuit then held that “[w]hat is critical is how a person of skill in the art would read the disclosure—not the exact words used.” The Federal Circuit noted that HEC's argument would elevate form over substance by creating a new rule that a limitation which is not expressly recited in the disclosure is never adequately described, regardless of how a skilled artisan would read that disclosure.
In the dissenting opinion, Chief Judge Moore agreed with HEC and concluded: “silence is not disclosure.” Specifically, the dissent notes that the Manual of Patent Examining Procedure (“MPEP”) states: “The mere absence of a positive recitation is not a basis for an exclusion.” MPEP § 2173.05(i).
Notably, the majority's decision seems not to disagree in principle. The majority appears to hold that the “mere absence of a positive recitation” is not enough and “silence alone is insufficient,” and holding that it is how a skilled artisan reads a disclosure that matters—noting that a written description may take any form, so long as a skilled artisan would read the disclosure as describing the claimed invention.
We strongly suspect that a request for rehearing en banc will be submitted and, regardless of the outcome thereof, this case appears to present a very interesting question for the Supreme Court to consider. We will be following the progress and expect to report further as the case proceeds.
 With respect to HEC's burden to overcome the district court's decision, the Federal Circuit held that whether a claim satisfies the written description requirement is a question of fact that, on appeal from a bench trial, is reviewed for clear error, meaning that the Federal Circuit requires having a “definite and firm conviction” that a mistake has been made before overturning the district court's factual findings.