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Microarray Patent Holders Relieved After Supreme Court Overturns Festo


Microarray patent holders can stop holding their breath after the US Supreme Court’s May 28 decision in the Festo vs. Shoketsu Kinzoku Kabushiki case: The decision restores protection to patents in cases where the patent claims were revised and narrowed during the patenting process, lawyers said.

In the unanimous decision, the Supreme Court partially overturned a ruling by a lower court that limited the enforcement in cases where there were claim revisions. It then set out a standard as to how to interpret the scope of patents in these cases.

“The decision is a relief to patentees that now have this extra ground to step outside the literal scope of their claims and argue that something is an equivalent,” said Kathleen Madden Williams, a partner and co-chair of the patent practice at Palmer & Dodge in Boston.

The decision, though, also leaves patent challengers some ammunition for arguments blocking infringement claims, and makes these claims more likely to be wrangled over in courtroom battles, according to patent lawyers. While the Supreme Court has set out a new standard, “We’re going to have case after case figuring out how that works,” said Bill Anthony, an intellectual property partner at the Silicon Valley office of Orrick, Herrington & Sutcliffe who represents Affymetrix and other technology companies.

Most microarray and genomics tools companies have been pleased by the ruling. “It really strengthens our patent portfolio,” said William Franzblau, vice president of legal affairs at Nanogen. “Someone can’t change one little thing and get around our patent.”

But others in the genomics and bioinformatics sphere, including Applera and IBM, had wanted the Supreme court to rule differently than it did, going so far as to file friend-of-the court, orAmicus briefs arguing that the Court should affirm a stricter standard for limiting patents that have been revised during the patenting process: These established companies took this more hard-line position, according to Anthony, because they had often been targets of individuals who effectively abused the patent process, patenting useless inventions in broad language that could cover major technologies, and then suing the deep pocket companies for infringement.

What the Court Held

In the ruling, the Court laid out the rules for when a narrowing of a patent claim during the patenting process (technically called prosecution), bars the patent holder from alleging that another inventor is infringing on the patent under the so-called doctrine of equivalents.

“The doctrine of equivalents allows the patentee to claim those insubstantial alterations that were not captured in drafting the original patent claim but which could be crafted through trivial changes, “ wrote Justice Anthony Kennedy in the Court’s opinion. “When, however, the patentee originally claimed the subject matter alleged to infringe but then narrowed the claim in response to a rejection, he may not argue that the surrendered territory comprised unforeseen subject matter that should be deemed equivalent to the literal claims of the issued patent.”

The Court went on to state, “the patentee should bear the burden of showing that the amendment does not surrender the particular equivalent in question.”

In other words, if Company A is trying to sue Company B for infringing on its patent, and Company B defends against that by showing that the Company A narrowed its patent language, Company A has to prove that this change to the patent language does not in fact narrow the patent’s scope to exclude Company B’s invention.

This second part is where the Supreme Court case differs from the Federal Circuit’s ruling. Under that ruling, any showing that the patent had been narrowed during prosecution created estoppel, barring a patent holder from arguing that the would-be infringer’s invention was “substantially equivalent” to the patented invention.

To illustrate these concepts, Williams has in the past compared a patent to a circle with a target in the middle. The target is the invention — say a microarray device — that the patent holder has patented. But since language is imprecise in describing the microarray device, the language creates a circle around the device. If the patent examiners initially reject the patent application because this circle is too big, and the patent holder then cuts out a niche in the circle to get around prior art (prior inventions in the patent process) or for other reasons related to patentability, the area removed by this revision is not protected by the patent. The patent holder is prevented, or “estopped” from enforcing the patent against infringers in the carved out area. However, under this new decision, the patent holder can argue that the revision that cut out the niche was not made for reasons related to patentability, and did not cut out language covering the allegedly infringing inventon.

The decision creates “a little penumbra beyond the literal scope” of the patent, said Beth Arnold, a biotechnology patent partner at Foley Hoag’s Boston office.

 Impact on Future Patents

This decision will impact the way that patent attorneys write and prosecute patents, according to lawyers. For genomics tools companies, this only highlights the importance of a skilled patent attorney to write and prosecute the patent in order to avoid making it vulnerable to the arguments of estoppel, according to Anthony. “Patent attorneys are now charged with clairvoyance,” he said. “They need to write the patent which in words today will cover tomorrow’s technology.” (Anthony added that he is not shilling for business, as he only does litigation, not patent prosecution.)

The clairvoyance should also be accompanied by a wise strategy of appealing, rather than revising patent applications in certain cases, other lawyers said. “In the past, a lot of times you would make a change that the examiner wants you to do, even though you think it is rather than appeal you do what you think is a trivial giveaway, but the patent examiner feels differently,” said Dick Evans, a patent attorney for Agilent. “Now people will be more willing to appeal [the examiners’ decision to reject the application] than to make an amendment” to the claims, Evans said. Also, he added, patent applicants might fight a little harder when they think the examiner is incorrect in rejecting their application, noting that his opinions are not an official Agilent position.

But Evans added that many firms have already been pursuing a more conservative strategy. “This decision hasn’t changed any of our patent positions or our assessments,” he said. “I can’t think of anyone [at Agilent] who would have relied on the full text of [the lower court’s Festo ruling] to make a commercial decision.”

Others had changed their patenting tactics after the lower court’s decision, said Arnold. “People went in with claims that they knew were allowable and went out from there,” she said.

This practice may still continue, given that the narrowing of claims can still limit a patent’s power.

“Writing narrowly is one strategy that is definitely favored by the Supreme Court decision,” said Williams. “It is very clear that if you are too aggressive in terms of breadth, you are vulnerable to this case law because you’re going to have to narrow the claims.”

Still, some patent lawyers say the new ruling may allow them to loosen up a bit. “Now we can patent more broadly. We don’t have to be frozen in doing prosecution,” said Liz Howard, a partner at the Silicon Valley office of Orrick, Herrington & Sutcliffe.


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