Divisional of Divisional Reaches Safe Harbor of 35 U.S.C § 121

Some may recall my “dissertation” on the case of Amgen Inc. v. F. Hoffman-La Roche Ltd. See CAFC: A Divisional By Any Other Name Is Not a Divisional .  In Amgen, the Federal Circuit made it clear that you had better characterize an application as a “divisional” if you wanted the benefit of the “safe harbor” provided by 35 U.S.C § 121.  And if you didn’t, you would face the consequence of an obviousness-type double patenting issue.

So does this “safe harbor” apply if you file a divisional of a divisional?  What if each of these divisionals has claims to more than one of the groups restricted in the original patent application?  Those were the questions that confronted the Federal Circuit in Boehringer Ingelheim International GMBH v. Barr Laboratories, Inc.  In responding to these questions, the entire Federal Circuit panel agreed that this “safe harbor” could apply to a divisional of a divisional.  Where the majority (Judges Linn and Prost) and dissent (Judge Dyk) diverged was on whether each of these divisionals, and especially the subsequent second divisional, could have claims to more than one of the restricted groups and still receive the benefit of this “safe harbor.”


The situation in Boehringer is fairly complex but the key facts relating to the “safe harbor” issues are as follows:

1.   The original application (the ‘947 application) contained 15 claims directed to certain benzothiazole compounds, their use (for lowering pressure or heart rate, for treating Parkinson disease or for treating schizophrenia), and methods for making these compounds.  The ‘947 application was subject to a restriction requirement where the patent examiner listed 10 groups of subject matter considered to be “independent and distinct inventions”:  (a) Groups I-V drawn to the compounds; (b) Groups VI-VII drawn to methods for making these compounds; and (c) Groups IX-X drawn to methods for using these compounds.  The Group II compound subject matter (pyrrolidinyl-substituted benzothiazoles) and the Group IX use subject matter (treating Parkinson disease) were elected in the ‘947 application which later issued as U.S. Pat. No. 4,731,374 (the ‘374 patent).

2.    During the pendency of the ‘947 application, a first divisional application (the ‘197 application) was filed which started with the original 15 claims.  The ‘197 application was later amended (in response to a rejection by a different patent examiner handling the ‘197 application) to include only use claims encompassing the Group VIII-X subject matter (with the exception of Group IX uses involving the Group II compounds elected in the ‘374 patent).  In other words, none of the claims in the ‘197 application covered the subject matter elected in the ‘347 patent.  Also, no restriction requirement was made by the patent examiner handling the ‘197 application.  The ‘197 application later issued as U.S. Pat. No. 4,843,086 (the ‘086 patent) which expired on June 27, 2006.

3.   During the pendency of the ‘086 patent (but after the ‘374 patent issued), which, like the ‘086 patent, started with the original 15 claims.  Also like the ‘086 patent, the 671 application was later amended to include only compound claims (other than the pyrrolidinyl-substituted benzothiazoles covered by the ‘374 patent) which encompassed the Group I and III-V compound subject matter.  As characterized by the majority panel opinion, these amended claims “[did] not cross the examiner’s lines of demarcation with either the claims of the grandparent [‘374 patent] or those of the parent [‘086 patent].”  These amended claims also covered a tetrahydrobenzothiazole more commonly known as pramipexole marketed under Boehringer’s (the patentee’s) brand name of Mirapex.

4.   The ‘671 application later issued as U.S. Pat. No. 4,886,812 (the ‘812 patent) approximately 6 months after the ‘086 patent issued.  The ‘812 patent’s original expiration date was December 12, 2006.  Boehringer  applied for patent term extension (under 35 U.S.C. § 156) based on approval of a New Drug Application (NDA) for its Mirapex drug which was alleged to be covered by Claims 1-4 and 7-10 of the ‘812 patent.  This extension was granted so that the ‘812 patent now expired on March 25, 2011 (1,564 days after the original expiration date).

On October 26, 2005, Mylan Pharmaceuticals (one of the alleged infringers) notified Boehringer of the filing of an Abbreviated New Drug Application (ANDA) for generic pramipexole.  Boehringer then filed a patent infringement suit again Mylan, which was then consolidated with an earlier patent infringement action against Barr Laboratories (who had also filed an ANDA for generic pramipexole).  As a defense and counterclaim, Mylan argued that the asserted Claims 3-5, 7, and 9-10 of the ‘812 patent were invalid for obviousness-type patenting in view of the ‘086 patent.  The district court agreed and held the ‘812 patent invalid for obviousness-type patenting.

In appealing the district court’s invalidity ruling, one argument again raised by Boehringer was its filing of a “retroactive” terminal disclaimer of the ‘086 patent (also referred to as the “reference patent”).  This terminal disclaimer was deemed “retroactive” because the ‘086 patent had already expired.  I won’t go into the details of discussing why this “retroactive” terminal disclaimer of the ‘086 patent failed.  The “bottom-line” was that the entire Federal Circuit panel agreed with the district court that this “retroactive” terminal disclaimer was ineffective to cure the alleged obviousness-type double patenting.

Boehringer then argued that the ‘812 patent was entitled to the “safe harbor” of 35 U.S.C § 121 which precluded a finding of obviousness-type patenting.  A majority of the Federal Circuit panel agreed based on its construction of this portion of the third sentence of 35 U.S.C § 121 (referred to in the opinion as the “as a result of” requirement):

A patent issuing on an application with respect to which a requirement for restriction under this section has been made, or on an application filed as a result of such a requirement, shall not be used as a reference either in the Patent and Trademark Office or in the courts against a divisional application or against the original application or any patent issued on either of them (emphasis added).

First, the entire Federal Circuit panel rejected Mylan’s argument that this “safe harbor” didn’t apply at all to a “divisional of a divisional.”  As stated by the majority panel, 35 U.S.C § 121 refers broadly to “’a divisional application’, and does not state that divisional must be a direct divisional of the original application.”

Second, regarding the “as a result of” requirement, Boehringer initially argued that this requirement should only apply to the ‘086 patent (i.e., the reference patent for the double patenting challenge), and not the ‘812 patent (i.e., the challenged patent).  Reading the literal language of the third sentence quoted above, I think Boehringer’s interpretation that the “as a result of” requirement only applies to the ‘086 patent (the reference patent) is the correct one.  But from reading the majority panel’s discussion of the prior Federal Circuit case, there appears to be too much precedential “baggage” suggesting to the contrary.  Accordingly, the majority panel opinion agreed with the district court that the “as a result of requirement” must be “satisfied by the ‘086 reference patent and the ‘812 challenged patent.”

But Boehringer prevailed on its next argument:  the challenged ‘812 patent also satisfied the “as a result” requirement.  The majority of the panel agreed, acknowledging that Boehringer hadn’t filed “separate divisional applications on each of the inventions grouped by the examiner in the restriction requirement.”  Instead, Boehringer had filed “two successive divisionals to different combinations of the inventions identified in the restriction requirement” which “neither violated the examiner’s restriction requirement nor risked loss of the safe harbor” of 35 U.S.C § 121.

According to the majority of the panel, in dividing out the claims to a non-elected inventions (as Boehringer had done), all that the “safe harbor” of 35 U.S.C § 121 required was “consonance with the restriction requirement.”  That there might be “overlap of claims to the independent and distinct inventions” was irrelevant, provided the prosecuted claims in the applications in “a divisional chain honor, as between applications, the lines of demarcation drawn by the examiner to what he or she considered independent and distinct inventions in the restriction requirement.”  The majority of the panel found such “consonance” in that the inventions claimed between the original ‘374 patent, the first divisional ‘086 patent, and the second divisional ‘812 patent didn’t “[cross] the examiner’s lines of demarcation of inventions identified in the restriction requirement.”

In allowing the restricted groups (or at least a portion of those restricted groups) to be collected into one or more divisionals (as Boehringer did), the majority of the panel in Boehringer achieved a very practical and pragmatic result which is consistent with (or at least not contrary to) the literal language of the third sentence of 35 USC § 121.  Most significantly, by permitting these restricted groups to be collected into one (or more) divisionals, the majority panel opinion still insured that the “demarcation line” set out by the examiner in restricting the groups in the first place wasn’t “crossed,” and thus there was no violation of the “spirit” of “consonance” required for the “safe harbor” to apply.  Also, if the examiner handling the divisional containing the collected groups of claims wanted to further restrict between these collected groups, nothing in the majority panel opinion in Boehringer prevents he/she from doing so.

Judge Dyk’s dissent takes a much more strict (and narrow) view of the “safe harbor” afforded by 35 USC § 121, and especially what the “as a result of” requirement means.  But as the majority of the panel (in my opinion) correctly observed, Judge Dyk interprets this requirement “too narrowly.”  Instead, Judge Dyk’s dissent appears to exalt “form over substance.”

Most importantly for restriction practice, Judge Dyk’s dissent makes no practical sense to me because it creates all kinds of potentially costly (and complex) problems in patent prosecution.  For example, Judge Dyk’s view would require a separate divisional to be filed for each of the restricted groups.  For Boehringer, that would have meant filing potentially 9 separate divisionals, with all the attendant expense and prosecution complexity.  That also creates a “Hobson’s choice” because if you fail to file claims in a divisional to cover anyone of those restricted groups, you’ll be faced with a potential “disclosed but didn’t claim” problem.

The holding in the Amgen case rested on a might be characterized as a “technicality” for denying the “safe harbor” under 35 U.S.C § 121.  By comparison, the majority opinion in the Boehringer case takes a more generous and pragmatic view of when this “safe harbor” applies to divisionals.  It remains to be seen which “tack” the Federal Circuit will take in interpreting future situations involving this “safe harbor.”

© 2010 Eric W. Guttag.


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