Biogen v. Mylan Written Description - What Does The Federal Circuit's Decision Really Mean?

December 8, 2021

Following up on my post last week (Dec 1.), I have read commentary about how the Federal Circuit’s decision in Biogen v. Mylan was incorrect. Is it really the case that the decision was wrong and that the Federal Circuit needs to address it en banc (or that the Supreme Court needs to address it)? 

Let’s look at the Mylan opinion and another recent Federal Circuit decision on written description, Indivior v. Dr. Reddy’s (November 24, 2021). In both cases, the Federal Circuit noted the fact-specific nature of a written description analysis. In Biogen, the court stated that “the written-description analysis is highly dependent on the facts of each case,” while in Indivior it stated that “written description cases are intensively fact-oriented.” The Federal Circuit’s focus on facts in a written description analysis is important and is affected by the context of each case when it reaches the court.

Biogen was an appeal of a district court decision, and the Federal Circuit employed a “clear error” standard of review, noting that appellate courts “must take into account the ‘unchallenged superiority’ of a district court’s ability to make witness-credibility determinations and findings of fact.” 

Indivior was an appeal from a PTAB decision in which the Federal Circuit employed a “substantial evidence” standard of review (“A finding is supported by substantial evidence if a reasonable mind might accept the evidence as adequate to support the finding”).

Both review standards substantially defer to the trier of fact, whether it is a district court or the PTAB. 

The Federal Circuit affirmed both the district court’s decision in Biogen and the PTAB’s decision in Indivior. Given that the Federal Circuit relied on the facts as determined by the district court or PTAB in these cases, it should not be surprising that the original decisions were affirmed owing to the “intensively fact-oriented” nature of the written description analysis.

As for the Biogen decision, as noted in my earlier post, it is interesting that a new inventor (O’Neill) was subsequently added to the patent application. If the original application actually demonstrated possession of the claimed invention by the inventor at the time of filing (per the written description analysis), would a new inventor have been added?

So is it really the case that the Biogen decision was wrong and needs to be corrected? The discussion above explains why it is not necessarily the case.