CAFC: A Divisional By Any Other Name Is Not a Divisional

The Federal Circuit, in Amgen Inc. v. F. Hoffman-La Roche Ltd, has made it clear that you had better characterize an application as a “divisional” if you want to the benefit of the “safe harbor” provided by 35 U.S.C § 121. And if you don’t, you’re going face obviousness-type double patenting problems.  The Federal Circuit in Amgen also went on to discuss the “muddy metaphysics” of obviousness-type patenting, including how to deal with the “time frame” issue recently raised in Takeda Pharmaceutical Co. v. Doll for overcoming double patenting of a process patent over an earlier issued product patent by presenting post-invention evidence of alternative processes of making the product.  How the Federal Circuit dealt with the “time frame” issue in Amgen will need to remain another story for another day because the subject of when the “safe harbor” applies will require an Excedrin, perhaps two.

Amgen involves a patent infringement battle over the production of the protein erythropoietin (“EPO”) using recombinant deoxyribonucleic acid (“DNA”) technology. EPO is a naturally occurring protein which stimulates the production of red blood cells. The production of EPO can be useful in treating blood disorders characterized by a low ratio of red blood cells to total blood cells, including anemia.

The Amgen case has enough issues in it give anyone a headache, and enough to keep me or any other patent scribe in knots for the foreseeable future. Not the least of these headaches is the tangled relationship between the five Amgen patents involved: U.S. Pat No. 5,441,868 (the ‘868 patent); U.S. Pat. No. 5,547,933 (the ‘933 patent); U.S. Pat. No. 5,618,698 (the ‘698 patent); U.S. Pat. No. 5,756,339 (the ‘349 patent); and U.S. Pat. No. 5,955,422 (the ‘422 patent). These five patents shared a common pedigree and specification in expired U.S. Pat. No. 4,703,008 (the ‘008 patent).  Nevertheless, the one I’m going to focus on deals with the “fork in the prosecution history road” that occurred in response to a restriction requirement made in the parent ‘298 application which led to the ‘008 patent, and which ultimately spawned these other five patents.

This restriction requirement pursuant to 35 U.S.C § 121 identified the ‘298 application as comprising six separate inventions. This then led to the filing of two subsequent applications (the ‘178 application and the ‘179 application). Ultimately, the ‘178 application led to ‘933 patent, while the ‘179 application ultimately led to the other four patents.

So much for the “Reader’s Digest” version of the pedigree of these five patents. What became the crux of the battle between Amgen and the three alleged infringers (collectively referred to as “Roche”) over the obviousness-type double patenting issue involving these five patents was how the ‘178 and ‘179 applications were identified, or more correctly “designated” by Amgen. For reasons which are not readily apparent and which are not explained in the Federal Circuit opinion, Amgen designated these two applications at the time of filing as “continuations,” not “divisionals.”

So why did it matter how Amgen designated these the ‘178 and ‘179 applications? Well, 35 U.S.C § 121 (entitled “Divisional applications”) says the following in the third sentence:

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, if the divisional application is filed before the issuance of the patent on the other application. (Emphasis added).

The “shall not be used as a reference” phrase is commonly referred to as the “safe harbor” of 35 U.S.C § 121. The 1996 Federal Circuit case of Applied Materials, Inc. v. Advanced Semiconductor Materials America, Inc. also held that this “safe harbor” shields applications filed as a result of restrictions requirement from double patenting problems, including obviousness-type double patenting.

The district court ruled that this “safe harbor” applied to three of the patents (the ‘933, ‘422, and ‘348 patents) resulting from the ‘178 and ‘179 applications against assertions of obviousness-type double patenting over the other two patents (the ‘868 and ‘698 patents), as well as the parent ‘008 patent. The basis for the district court applying the “safe harbor” was simply that the ‘178 and ‘179 applications were filed in response to the restriction requirement in the ‘298 application. In fact, the district court referred to these two applications as “divisional applications” even though the ‘178 and ‘179 applications were designated at the time of filing as “continuation applications.”

Roche protested that the “safe harbor” didn’t apply because the ‘178 and ‘179 applications were designated as continuations, not divisionals. Roche pointed to the title of 35 U.S.C § 121 (“Divisional Applications”), as well as the specific references in the third sentence to “divisional applications” as excluding “continuation applications” from the protection of the “safe harbor.” Because the 933, ‘422, and ‘348 patents resulted from the ‘178 and ‘179 applications which were designated by Amgen as “continuations,” Roche argued that the “safe harbor” didn’t shield these three patents from obviousness-type double patenting.

By contrast, Amgen urged that how the ‘178 and ‘179 applications were designated at the time of filing didn’t matter because these applications, in substance, qualified as “divisional applications” under the “safe harbor.” Amgen even pointed to the definition of “divisional application” in MPEP § 201.06:

A later application for an independent or distinct invention, carved out of a pending application and disclosing and claiming only subject matter disclosed in the earlier or parent application, is known as a divisional application or “division.”

Because the ‘178 and ‘179 applications conformed to the definition of “divisional application” in MPEP § 201.06, Amgen argued that the 933, ‘422, and ‘348 patents which ultimately resulted from these applications were entitled to the “safe harbor.”

The Federal Circuit’s short answer to this long tale was that the “safe harbor” didn’t apply to these three patents. Instead, the Federal Circuit agreed with Roche that “because the ’178 and ’179 applications were filed as continuation—rather than divisional—applications, the ’933, ’422, and ’349 patents do not receive the [“safe harbor”] benefit of [35 U.S.C.] § 121.” The Federal Circuit relied upon its recent opinion in Pfizer, Inc. v. Teva Pharmaceuticals USA, Inc. that the “safe harbor” didn’t apply to a continuation-in-part application. Because Pfizer noted the absence of anything in the legislative that suggested the “safe harbor” was “directed to anything but divisional applications,” the Federal Circuit in Amgen held that the “safe harbor” also didn’t “protect continuation applications or patents descending from only continuation applications.”

The Federal Circuit also refuted Amgen’s “in substance” argument by hoisting Amgen on its own petard: “Amgen does not dispute that it denominated the ’178 and ’179 applications continuations, that it checked the continuation application box on the submitted form, or that its applications met the PTO’s definition of a continuation application in MPEP § 201.07.” While Amgen might have convinced the district court based on this “in substance” argument, the Federal Circuit said “we are not likewise convinced.” Instead, the Federal Circuit concluded by saying “[w]e decline to construe ‘divisional application’ in [35 U.S.C.] § 121 to encompass Amgen’s properly filed, properly designated continuation applications.”

Ouch! So there you have it: how you designate or name an application matters very much for whether you’re going to receive protection under the “safe harbor” of 35 U.S.C. § 121.

EDITOR’S NOTE: For a discussion of the claims, ruling and permanent injunction, which still stands as a result of the Federal Circuit decision, see what Patent Doc Kevin Noonan had to say in what looks like Part 1 of a series on the case.


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Join the Discussion

3 comments so far.

  • [Avatar for patent leather]
    patent leather
    September 17, 2009 01:34 pm

    However, I’m assuming all this could have been easiy cured by filing a terminal disclaimer with the continuation. I’ll be sure to be checking all my cases for this issue…

  • [Avatar for EG]
    September 17, 2009 11:15 am


    I hear you, but I’m not sure I would characterize this as a “minor technical error.”. Amgen made the deliberate choice to designate the two key applications (‘178 and ‘179) as “continuations.” What I still can’t figure out is why Amgen choose to designate these applications as “continuations.” The benefit of doing so (versus designating these applications as “divisionals”) escapes me.

    In defense of the Federal Circuit’s opinion in Amgen, 35 USC 121, including the title of it, only refers to “original” and “divisional” applications. Accordingly, their view that designating the application as a “divisional” that is being filed in response a restriction requirement (also necessary under 35 USC 121 to get the “safe harbor”) is reasonable to make clear that the benefit of the “safe harbor” applies.. For example, a “continuation” application could be to present claims different from or even broader than those presented in the “original” (parent) application, i.e., is not in response to a restriction requirement. Again, Amgen made the designation of “continuation,” not the Federal Circuit.

    Thanks for your comment and thoughts.

  • [Avatar for Dale B. Halling]
    Dale B. Halling
    September 17, 2009 10:57 am

    Another case of formalism being more important than substance. Because of a minor technical error an inventor loses their rights. How does that promote science and the useful arts?

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