In Amgen, Inc. v. Sanofi, [2017-1480](October 5, 2017), the Federal Circuit found that the district court erred by excluding Appellants’ evidence
regarding written description and enablement, and improperly instructed the jury on written description, so the Federal Circuit reversed-in-part the judgment below and remanded for a new trial on written description and enablement (concluding that defendants/appellants were not entitled to JMOL of no written description and no enablement.

The case relates to U.S. Patent Nos. 8,829,165 and 8,859,741 on  antibodies that help reduce low-density lipoprotein cholesterol (LDLC),
or “bad cholesterol.”  The district court  excluded Appellants’ evidence about antibodies, including Appellants’ infringing Praluent, developed after the patents’ priority date of January 9, 2008, reasoning that because the
evidence did not illuminate the state of the art at the time of filing,” it was not relevant “to determine whether there is sufficient disclosure of the claimed invention.”

However, the Federal Circuit found that Appellants were not offering
post-priority-date evidence to show that Appellees’ claimed genus is not enabled because of a change in the state of the art. Instead, Appellants offered Praluent and other post-priority-date antibodies to argue that the
claimed genus fails to disclose a representative number of species. As explained above, the use of post-priority-date evidence to show that a patent does not disclose a representative number of species of a claimed genus is proper. It was thus legal error for the district court to categorically
preclude all of Appellants’ post-priority-date evidence of Praluent and other antibodies. The Federal Circuit reversed the district court’s decision and remanded for a new trial on written description.

The Federal Circuit also found district court’s improper exclusion of post-priority-date evidence requires a new trial on enablement as well. Under the enablement requirement, the specification of a patent must teach
those skilled in the art how to make and use the full scope of the claimed invention without undue experimentation.  Appellants purportedly sought to introduce post-priority-date evidence showing that Appellees engaged in lengthy and potentially undue experimentation to enable the full scope of the claims. Such evidence could have been relevant to determining if the claims were enabled as of the priority date and should not have
been excluded simply because it post-dated the claims’ priority date.

The Federal Circuit turned to the jury instructions on written description.  The Federal Circuit said that the district court correctly instructed the jury that in order to satisfy the written description requirement, a patentee may disclose either a representative number of species falling within the scope of the genus or disclose structural features
common to the members of the genus so that one of skill in the art can visualize or recognize the members of the genus.  However the district court went on to instruct that “the correlation between structure and function may also be satisfied by the disclosure of a newly characterized antigen by its structure, formula, chemical name, or physical properties if you find that the level of skill and knowledge in the art of antibodies at the
time of filing was such that production of antibodies against such an antigen was conventional or routine.”  The Federal Circuit this instruction was not legally sound and is not based on any binding precedent.

The Federal Circuit said that this instruction improperly allowed a jury to find adequate written description merely from a finding of the ability to make and use the invention.  The Federal Circuit said that an adequate written description must contain enough information about the actual makeup of the claimed products—“a precise definition, such as by structure, formula, chemical name, physical properties, or other properties, of species falling within the genus sufficient to distinguish the genus from other materials,” which may be present in “functional” terminology “when the art has established a correlation between structure and function.”
However, it is still contested whether the that knowledge of the chemical structure of an antigen gives the required kind of structure-identifying information about the corresponding antibodies.  The Federal Circuit said that Section 112 requires a “written description of the invention,” not something that is not the invention.

The Federal Circuit affirmed the denial of JMOL of lack of written description and enablement, because with the exclusion of post-priority date evidence the record was incomplete to determine whether there is in fact a lack of written description and enablement.  The Federal Circuit also affirmed JMOL of non-obviousness, finding that the district court properly excluded the proffered prior art.  These references, two PCT applications were filed after the priority date, but claimed priority to provisional applications filed before the priority date.  The Federal Circuit noted that appellants did not proffer any evidence showing that the provisional applications contained representative species or common structural
elements sufficient to satisfy the written description requirement for the monoclonal antibodies claimed in the PCT applications.  Similarly, the Federal Circuit noted, Appellants provided no evidence that the claims of the PCT applications were enabled by the provisional application. Because the district court properly excluded the prior art relied upon by appellant, the court’s grant of JMOL of non-obviousness was proper.

Finally, the Federal Circuit vacated the permanent injunction because it vacated the district court’s judgment as to written description and enablement, and was remanding the case for a new trial.