Is There Another Chink In Your Patent Armor?

his article was first published in the August 5, 2009 edition of The Legal Intelligencer.

It seems these days that a patent holder can’t catch a break. In the last two years, there has been a noticeable weakening of patent rights, presumably as a reaction to the perception that lower quality patents were issuing from the U.S. Patent & Trademark Office.

We have seen the judiciary give licensees an incentive to challenge the validity of their licensor’s patents ( MedImmune v. Genentech ). We have seen the judiciary declare that the patent holder’s express statutory right “to exclude others” may not always permit exclusion of others ( eBay v. Mercexchange ). We have seen the same judiciary attempt to make it harder to establish willful infringement ( In re Seagate Technology LLC ), and a likely endorsement of that change is apparently going to be adopted by Congress if the question of damages can ever be resolved in the pending Patent Law Reform Bills.

Now comes yet another decision worthy of conversation among those of us who are interested in finding ways to construct stronger patents for our clients while simultaneously balancing the rights of clients to challenge patents that fail to meet the statutory prerequisites for patentability. In Agilent Technologies Inc. v. Affymetrix Inc. , one panel of the U.S. Court of Appeals for the Federal Circuit recently continued a trend started some time ago, namely interpreting a statutory provision generally thought to define one prerequisite for patentability to actually encompass two separate prerequisites. Now in order to understand why this is actually quite important, one must consider the statutory language and the development of the law around it that got us to this point. 

The statute, 35 U.S.C. § 112 paragraph one, states, in relevant part: “The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains … to make and use the same … .”

In Agilent , and in certain cases preceding Agilent , the Federal Circuit has held there are two distinct elements within this provision. First, the specification must contain a written description of the invention, and second, the specification must enable one skilled in the art to make and use the invention. This was made somewhat clear back in 1991 in the Federal Circuit case Vas-Cath v. Marhurkar.

In Vas-Cath , the court wrote: “The purpose of the ‘written description’ requirement is broader than to merely explain how to ‘make and use’; the applicant must also convey with reasonable clarity to those skilled in the art that, as of the filing date sought, he or she was in possession of the invention.” This begs the question: If it explains how to make and use the invention (i.e., it is enabling), does it not follow that it necessarily shows that the applicant possessed the invention? 

The confusion lies in the fact that the statute at one point was generally believed to have only one requirement — simply that the written description had to be adequate to enable the practice of the invention. At least one panel of the Federal Circuit has expressed what seems to be a slight minority view of the present 12 circuit court judges, namely that a correct reading of paragraph one does in fact lead to the conclusion that if an invention is enabled, an adequate written description is subsumed. Other panels, however, have laid the groundwork for the recent Agilent decision. It should be noted that just two days before the Federal Circuit decision came out in Agilent , a petition for rehearing en banc was filed in Federal Circuit case Ariad Pharmaceuticals Inc. v. Eli Lilly & Co .

The first question raised in the petition is: “Whether this Court has erred by ‘engrafting … a separate written description requirement onto section 112, paragraph 1.'” The petition focuses on the split among judges on the Federal Circuit, and argues that the court’s written description analysis is not consistent with the plain text of the statute. 

A resolution of the issue through this case is particularly important because the written description controversy is especially problematic in the biotechnology field. This reality is based on the fact that the Federal Circuit declared invalid certain claims to a genus as violative of the written description requirement essentially because not all species of the genus were presented in the specification. A full review of this scenario is well beyond the scope of this article, but the petition for rehearing en banc in Ariad will be closely watched by many.

In order to understand the current state of affairs, it is helpful to recognize that the written description controversy arose in the context of new matter determinations. It is well settled that any amendments to the claims of the patent application can not add new matter to the application. In other words, the claims as amended must be “supported” by the original specification or the specification of the application to which the currently amended case claims priority. Thus, the issue becomes focused on what exactly is meant by “support” or “new matter” in the context of a particular claim amendment. What level of specificity is needed in the specification to establish that a claim amendment is supported by the original text?

One early example of this issue is factually relatively simple. In re Barker , a case before the Court of Customs and Patent Appeals (the predecessor of the Federal Circuit), involved the manufacture of shingle panels. The text described the making of panels having eight to 16 shingles on a panel. The claim ultimately was directed to a panel having at least six shingles. The CCPA found that although the text certainly enabled someone to make a six-shingle panel, it did not demonstrate that the applicant possessed the six-shingle panel as a part of its invention at the time it filed its application. (An interesting dissenting opinion said: “I cannot see how one may, in ‘full, clear, concise and exact terms,’ enable the skilled to practice an invention, and still have failed to ‘describe’ it.”)

Turning now to the continuing saga of modern day written description, in Agilent Technologies , Agilent and Affymetrix disputed which party was the first to invent a particular method of mixing a fluid. Agilent filed an application for the method on Aug. 21, 1998, and obtained a patent on Feb. 4, 2003. The issued Agilent patent contained a claim that required several steps and specific elements, in addition to which was the limitation that the method include providing a fluid in a closed chamber into which a bubble is provided and moved to cause mixing. Affymetrix believed it had invented the method before Aug. 21, 1998. It had filed its original application for a patent as early as June 7, 1995, and was still prosecuting continuation applications in that series after Feb. 4, 2003, at which time it copied a claim from the issued Agilent patent and provoked an interference proceeding so that the Board of Patent Appeals and Interferences could determine who was actually the first to invent the method. Because Affymetrix was the senior party (having filed first), Agilent had the burden of showing that it invented the method before Affymetrix.

Agilent argued to the board that the Affymetrix application did not describe the invention adequately under 35 U.S.C. § 112 paragraph 1 to show “actual possession of the bubble-mixing part of the invention.” The board disagreed, noted that the Affymetrix application did show support for the entire claimed invention, and awarded priority to Affymetrix, thereby canceling Agilent’s claims. The district court agreed with the board. The Federal Circuit did not and reversed.

The Federal Circuit reviewed what mixing techniques were present in the Affymetrix application. It found that bubbles were used in one of the disclosed techniques, but they were used in a container that was not closed. Other techniques showed a closed container, but those did not use bubbles. Moreover, the court concluded that although several mixing techniques were present in the Affymetrix application, the specific method of mixing recited in the claim, namely introducing fluid into a closed container and using bubbles to mix it, was not. It therefore held that Affymetrix did not “teach the claimed method” in its original filing.

In so doing, the Federal Circuit wrote that the issue is whether “the district court properly granted Affymetrix’s motion for summary judgment that the [Affymetrix] application shows adequate possession of the claimed invention at the time of invention [sic — filing], the written description requirement of § 112 para. 1.” It thus completely equated the written description requirement with a showing of “adequate possession” separate and apart from the enablement requirement.

It is arguable whether Agilent really changed the standard set forth in Vas-Cath for determining what constitutes “adequate possession” of the invention, but what seems less controversial is that it at least tightened the standard. In Vas-Cath , the court wrote that the purpose of the “written description” requirement is to convey “with reasonable clarity to those skilled in the art” that the applicant possessed the invention. In Agilent , the court seemed to be looking for explicit, unequivocal statements in the specification to support a claim amendment. This rigidity is likely to open up more patents to a validity attack under the statutory provision, which originally was only intended to ensure that the patent holder fairly enabled the public to use his invention once the patent exclusivity expired. 

What does this mean to the stakeholders? If and until the issue is resolved clearly, anyone seeking to invalidate a patent should look closely at all claim amendments made during prosecution to ascertain whether they violate the “adequate possession” rule of the “written description” part of § 112 paragraph 1. As a part of this review, careful attention should be paid to any and all prior applications in the series to determine if a priority date can be moved forward in time, thereby expanding the amount of prior art that can be considered. This analysis should not only be used to examine claim amendments that broadened the claim, but also those that narrowed it. To the extent the priority date can be moved forward, not only does additional prior art become available, but also acts by the patentee such as sales, offers for sale or publication.

Of course, taking an invalidity position based solely on the written description requirement is not without peril. The accused still bears the burden of proof by clear and convincing evidence. And even the Federal Circuit has recognized for many years how fact sensitive these determinations are. In Vas-Cath , quoting a previous opinion, the court said: “It should be readily apparent from recent decisions of this court involving the question of compliance with the description requirement of § 112 that each case must be decided on its own facts. Thus, the precedential value of cases in this area is extremely limited.”

But despite the apparent challenges of succeeding with an invalidity argument based on the written description requirement, it should be noted that there seems to be a resurgence in its use as the courts continue to reign in the power once more boldly wielded by the patent holder.


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