In Jang v. Boston Scientific, the Circuit takes on the doctrine of ensnarement, affirming a district court’s grant of JMOL based on the patentee’s inability to develop a hypothetical claim that covered the accused stent but did not ensnare the prior art. In Smith, the Circuit reverses an overly broad BRI, ruling that the issue is not whether the specification affirmatively “proscribes or precludes” an examiner’s broad reading of a claim, but rather whether the interpretation is one that corresponds with how the inventor describes the invention in the specification.

Thanks to one of my newer colleagues, Aaron Haleva, for his help with this week’s report.

Pete Heuser

Jang v. Boston Scientific Corp., Fed. Cir. Case 2016-1275, 1575 (September 29, 2017)

In the fourth time this case has been to the Circuit, the panel affirms the district court’s denial of Dr. Jang’s motion for JMOL as to literal infringement and its vacatur of the jury verdict of infringement under the doctrine of equivalents (“DOE”).

Dr. Jang’s invention is to a coronary stent. At trial, the jury concluded that there was no literal infringement. As to this verdict, Dr. Jang appeals the denial of JMOL, arguing that no reasonable jury could have so found. Dr. Jang was able to obtain a verdict of infringement under the DOE, but the district court vacated that verdict because Dr. Jang failed to provide an acceptable hypothetical claim for an ensnarement analysis that did not also ensnare the prior art.

In 2002, Dr. Jang assigned his ’021 patent to Boston Scientific (“BSC”) for $50 million, with the understanding that if BSC ever developed a stent that was covered by the ’021 patent, BSC would owe Dr. Jang royalties up to an additional $110 million. The issue here is whether BSC’s Express stent is one such stent.

Dr. Jang filed suit against BSC to recover the additional royalties and BSC requested ex parte reexamination. BSC also moved to amend its answer to allege that if the patent was invalidated in the reexamination, it did not owe already-accrued royalties. That motion was denied, the district court deeming a ruling of invalidity irrelevant as to whether BSC owed Dr. Jang for past royalties. After the PTO invalidated all of the claims in the reexamination, BSC used the same tack and moved for summary judgment that it did not owe royalties for royalties accrued before the PTO ruling, but the district court denied that motion as well.

Prior to trial, BSC argued that Dr. Jang’s DOE theory would ensnare the prior art, referencing three prior art patents. The district court decided to conduct a post-trial ensnarement hearing in the event the jury returned a verdict of infringement under the DOE. The jury subsequently ruled that there was no literal infringement but because the jury found infringement under the DOE, the district court conducted an evidentiary hearing on ensnarement. In that hearing, Dr. Jang presented hypothetical claims that he argued established a range of equivalents to which he believed he was entitled, above and beyond the actual scope of his asserted claims, that would be broad enough to literally cover BSC’s Express stent, yet not so broad that it would be unpatentable over the prior art. However, the district court disagreed and vacated the jury verdict of infringement under the DOE.

The panel begins its analysis of the ensnarement issue by citing its 2009 DePuy Spine v. Medtronic case, which held that a DOE theory cannot be asserted if it will encompass or ensnare the prior art “even if a jury has found equivalence as to each claim element.” The burden of producing evidence of prior art to challenge a hypothetical claim rests with an accused infringer, but the burden of proving patentability of the hypothetical claim rests with the patentee. Because the panel finds that Dr. Jang failed to submit a proper hypothetical claim that did not ensnare the prior art, the district court was correct that he was unable to meet his burden of proving his DOE theory. Again citing DePuy, the panel rejects Dr. Jang’s argument that BSC should have been barred from presenting its ensnarement defense because BSC was not allowed to challenge the validity of the asserted claims. The panel rules that the ensnarement inquiry has no bearing on the validity of the actual claims, as the claims will remain valid whether or not Dr. Jang persuaded the panel that he is entitled to the range of equivalents sought here.

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In Re: Smith International, Inc., Fed. Cir. Case 2016-2303 (September 26, 2017)

The Circuit overturns the Board’s upholding of an examiner’s rejection of several claims in an ex parte reexamination because the rejection was based upon an “unreasonably broad” claim construction. The decision provides needed guidance as to what constitutes the broadest reasonable interpretation (“BRI”) in construing patent claims.

Smith is the owner of an ’817 patent, which is directed to an expandable tool used in an oil drilling assembly. The tool is to be positioned within a wellbore, and it has a “body,” essentially an outer housing covering the entire tool.  Smith’s corporate parent Schlumberger sued Baker Hughes for infringement of the patent, and Baker Hughes responded by requesting ex parte reexamination. 

Three independent claims were rejected by the examiner as either being anticipated by Eddison or as being obvious in view of Eddison and two other references.  Each of the rejected claims recited the term “body” without further limitation. In its appeal to the Board, Smith argued that, while Eddison refers to a “body,” it is not an outer housing, and does not provide a cover for the entire length of the Eddison drilling tool. It actually fits over a “mandrel” which constitutes the entire upper portion of the Eddison tool. Smith argued that the proper construction of “body” is “an outer housing”—which was not taught by Eddison. The Board rejected that argument, noting that “body” is a broad term that may encompass other components such as “mandrel” and “cam sleeve.” The term “body” is recited in the claims without further limiting features, and the specification neither defines the term nor prohibits the examiner’s broad reading of it. 

The Circuit rules that, even when giving claim terms their BRI, the Board cannot construe claims “so broadly that its constructions are unreasonable under general claim construction principles,” citing to its 2015 decision in Microsoft v. Proxyconn. There is no dispute that the specification consistently describes and refers to the body as a component distinct from others, such as a mandrel or piston.  Thus, reading these latter elements from a prior art reference on the patent’s recitation of “body” is improper. 

The correct inquiry in giving a claim its BRI is not whether the specification affirmatively “proscribes or precludes” an examiner’s broad reading of a claim, but rather whether “it is an interpretation that corresponds with what and how the inventor describes this information in the specification.”  

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