Eye Therapies v. Slayback Pharma – Fed. Cir. Enhances the Scope of “Consisting Essentially”

Posted on July 13, 2025 by Warren Woessner

In Eye Therapeutics, LLC, v. Slayback Pharma, LLC., Appeal no. 2023-2173, (Fed. Cir., June 30, 2025), a panel of Judges Scarisi, Stoll and Tramto reversed a Board decision that the claims of U.S. Pat. No. 8,293,742 were invalid. Claim 1 of the ‘742 patent reads

  1. [“CEO”] administering brimonidine [“brim”] to a patient having an ocular condition wherein brim is present at a concentration between about 0.0l% by volume and about 0.05% by volume.

Brim is a vasodilator that reduces eye redness. As filed, the claimed method was one “comprising” brim. The comprising of method claim left the claim open to the inclusion of other active ingredients. The Examiner rejected the claims as anticipated by Dean, U.S. Pat. No. 6,242,442 that disclosed a method of administering a composition comprising brim and brinzolamide [“brin”]. Brin is used to treat glaucoma. Eye Therapeutics [“ET”] amended the claims to recite the “semi-open-ended” or “partially closed”,  preamble “consisting essentially of” [“CEO”]. It argued and the Examiner agreed that the amended claims were not anticipated because the claimed method does not require the use of any other active ingredients.

The Board reversed, relying on the typical meaning of CEO, that it leaves the claim open to unlisted ingredients that do not materially affect the basic and novel properties of the invention. The Board reasoned that to read the prosecution history to prohibit the use of any other active ingredients would construe the semi-open-ended transition phrase CEO  to have the same scope as the closed transition phrase “consisting of”.

The panel disagreed, but went beyond  the Examiner’s rationale that the claims distinguished Dean because they did not require the use of any other actives. ET essentially threw a Hail Mary argument that the panel caught for their rationale:

“ET contends the prosecution history supports an atypical meaning of CEO, as the applicant ‘expressly argued that the amended claims preclude the use of other active ingredients and that a basic and novel property of the invention is the administration of brim without other therapeutic drugs. We agree with ET that the prosecution history informs an atypical meaning of CEO in the 742 patent.” [emp. Added].

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“ Given ET’s arguments distinguishing Dean and definitional use of ‘i.e.’ to equate its claimed ‘methods CEO administering brim’ with methods that do not include administering other active agents, the appropriate interpretation of ET’s representation that the claimed methods ‘do not require’  agents other than brim is that the claimed methods preclude the use of such agents.”

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“Under the appropriate construction of CEO , the claimed methods exclude compositions that contain active agents other than brim, undermining the Board’s conclusion.”

The Board had agreed with Slayback that CEO would effectively be converted into “consisting of”, and I can’t see why that isn’t so. If CEO is read to exclude other actives, it is difficult to see what’s left, except for inert carriers and other adjunct agents, and they would be permissible under the traditional or the enhanced CEO.

 

 

 

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Sigray, Inc. v. Carl Zeis X-Ray Microscopy, Inc.—When does “No” Projection Magnification Mean “No”?

Posted on June 10, 2025 by Warren Woessner

In Sigray, Inc, v. Carl Zeis X-Ray [“Zeiss”], appeal 2023-2211 (Fed. Cir., May 23, 2025), the panel reviewed the Board’s decision in an IPR in which Claims 1-6 of Zeiss patent no. 7,400,704 were held not to be unpatentable over Jorgensen. Claim 1 of the ‘704 patent reads as follows:

As explained by the panel:

“Projection magnification…utilizes diverging rays that spread out as they travel. The distance between the rays increases after interacting with the sample but before being received by the detector. As a result, the generated image is larger than the sample itself, …  A larger distance between the source and the sample or a smaller distance between the sample and the detector will result is less magnification.”

The panel described the Jorgensen paper as applying a similar x ray system that describes all of the elements of Claim 1 except for the “magnification of the projection phase is between 1-10 times”. Jorgensen discloses attempting to reduce the projection magnification by providing a large distance between the sample and the source and a short distance between the sample and the detector. Jorgensen additionally descried using collimation – passing the beam through a lead-wrapped brass tube to further reduce the divergence of the beam—some divergence beyond strictly parallel rays is necessary to magnification.

After a succinct discussion on the legal standards of inherent anticipation: viz. “A limitation is inherently disclosed ‘when the reference discloses prior art that must necessarily include the unstated limitation’”. The panel went on to agree with Sigray that the Board had improperly construed Clams 1-6 to exclude small amounts of divergence that would, in turn, cause some projection magnification “only slightly greater than one.”

The evidence relied upon by the Board was, in part, the “aspirational” language in the Jorgensen paper that it is not attempting to achieve magnification. The paper does not address whether magnification is inherently present. The panel also relied on experts’ scientific “waffle words” that regularly appear in the literature and during testimony when the scientist/expert does not want to appear absolutist – such words noted by the panel as evidencing reduced divergence include “nearly parallel X-ray beam”, “essentially parallel”, and “greatly reduce”. The panel pointed out that “Reduce does not mean eliminate.”

The panel went on to hold that “The only evidence supported conclusion is that Jorgensen contains a beam diverging at the sample, which necessarily produces projection magnification over 1. As such, Claim 1 is anticipated by Jorgensen.”

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Regents of the U. of Cal. v. Broad Inst. – “Just The Facts, Ma’am.”

Posted on May 26, 2025 by Warren Woessner

The central theme in this interference decision involving U.S. Pat. No. 8,697,359 is the amount and type of evidence required to support the conception of an invention. Joe Friday wanted the witness to focus on the facts of the matter, a focus that the Fed. Cir. found that the Board lacked.

In The Regents of the University of California v. Broad Institute, Appeal no. 2022-1594 (Fed. Cir., May 12, 2025), the PTAB had awarded a priority date to Broad that made them the senior partly, even though the Regents had given a presentation and published a paper in Science magazine describing the invention that spurred Broad (“Zhang”) to begin researching the same gene-editing  CRISPER-Cas system. The two groups addressed the question of whether or not the system would work in eukaryotic cells, particularly in a form comprising two linked RNA linked into a “single guide” RNA.

Regents also published its initial work on the single guide system in June 2022. Regents filed three provisional patent applications, P1 on May 25, 2022, P2 on Oct. 12, 2022, and P3 in Jan. 2023. The PTAB rejected Regents asserted date of reduction to practice of August 9, 2022 and only granted Regents’ priority claim to the Jan. provisional. The PTAB also found that P1 and P2 failed to meet the written description requirement of s. 112. The Board also awarded a priority date of October 5, 2022 to Broad, on the basis of a paper that Zhang submitted to Science on that date.

The Fed. Cir. held that the Board legally erred “by conflating the distinct legal standards for conception and reduction to practice” and held that the Board erred by requiring Regents’ scientists to know their system would work at the conception stage.

The Fed. Cir. also agreed with Regents that the court erred in solely focusing on the back and forth statements by the Regents scientists about their progress and failures in getting the system to reproducibly transform eukaryotic cells, without considering whether Regents “actually and substantively modified the system” to the extent that Regents did not initially have a “definite and permanent idea” of the “complete invention as it will be used in practice.”

“The appropriate analysis should turn on whether Regents scientists ‘had formed the idea of their use [for transforming eukaryotic cells] in sufficiently final form that only the exercise if ordinary skill remained to reduce it to practice’—more than a general hope”. [distinguishing Hitzeman v. Rutter].

The court also found that it was legal error for the Board to “categorically disregard evidence of purported experimental success by others” and to disregard Regents’ arguments that, despite difficulties, only routine methods as used by the POSA were required to reduce the invention of count I — a functional CRISPER system — to practice. The court vacated the Boards decision on conception and remanded for the Board to decide on conception under the “proper application of the legal framework.”

Regents are not in the legal clear, because the court, relying on Ariad, held that P1 and, by implication, P2 failed the written description requirement (WDR) of s. 112.

“[/t] test for sufficiency is whether the disclosure ‘reasonably conveys to those skilled in the art that the inventor had possession of the claimed invention as of the filing date…This test and its concept of possession required us to determine how a [POSA] would understand the four corners of the specification” [citing Ariad]

The court held that the Board did not err in finding that the system was complex and unpredictable and that the P1 applicants  had failed to disclose “specific instructions or conditions necessary for CRISPER-Cas9 activity in a eukaryotic cell, or an indication that no specific instructions or conditions were necessary.” The court agreed with the Boards ruling that a [POSA] would not understand P1 to show or establish possession.

The Board had noted that there were no working examples in P1 but did not treat this as dispositive, and the court agreed with the Board’s application of the possession test. The court noted Broad’s argument that “the unpredictable nature, well-known obstacles, and prior failures and difficulties in adapting prior art prokaryotic cells to eukaryotic cells’ support that P1 lacks written description.

Since the parties claim construction arguments are specific to this case, they are of less interest. The question remains, however, if Regents can establish conception, perhaps based at least in part on their publications.

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Regeneron v. Mylan, “It Ain’t Necessarily So.”

Posted on April 27, 2025 by Warren Woessner

Regeneron v. Mylan, appeal nos. 2024-2058, 2024-2147 (Fed. Cir., March 5, 2025) is the most recent appeal in a long line of Hatch-Waxman suits filed by Regeneron to block generic versions of its VEGF antagonist (or “trap”) EYLEA®, that is a used to treat angiogenesis in the eye. Regeneron’s asserted patent, U.S. Patent No. 11,084,865 is part of a large family of continuations, one of which also includes U.S. Patent No. 9,340,594. The ‘594 patent expired in 2021 and was argued to be a reference patent that rendered the later-issued ‘865 patent invalid for obviousness-type double-patenting (“ODP”).

The central argument raised by defendant-appellant Celltrion was that the claims of the ‘865 patent that recited the stability of the claimed formulation were anticipated or obvious in view of claims of the ‘594 patent. Apart from the recitation of structural features of the VEGF trap and the other ingredients in the formulation, the relevant stability elements in the ‘594 patent are that the formulated VEGF trap is stable for at least 4 or 5 months. The recitation of the stability element in claim 1 of the ‘865 patent is that “at least 98% of the VEGF antagonist is present in native conformation following storage at 5 degrees C. for two months as measured by size exclusion chromatography”.

The district court, in denying Celltrion’s arguments that it was entitled to a preliminary injunction, found that the 98% native conformation claim limitation is neither inherent nor obvious in the subject matter claimed in claim 5 (4 months). On appeal, Celltrion argued that the district court erred in declining to construe “stable” to require the more detailed recitation of stability in claim of the ‘865 patent. The district court rejected this interpretation and found that the “specification of the ‘594 patent has numerous descriptions of stability beyond simple 98% native conformation as measured by SEC.” The district court noted that the specification describes multiple aspects of stability and multiple ways to determine stability, not just SEC.  The Fed. Cir. agreed and ruled that there was no express anticipation of the asserted ‘865 patent.

Celltrion’s argument that the 98% native VEGF claim limitation is inherent in claim 5 of the ‘594 patent was unavailing. The district court found that claim 5 does not “necessarily” meet the 98% native conformation limitation:

“That the practice of ‘594 claim 5 sometimes results in 98% native conformation is insufficient; inherency requires that the 98% native conformation limitation be present necessarily, not just possibly or probably.” The Fed. Cir. agreed. This is a heavy burden, both on litigators tasked with proving anticipation when claim elements are missing, as well as on applicants who need to distinguish prior art than may or may not anticipate. Of course, in this case, the courts agreed with Sportin’ Life in a line from Show Boat that attorney argument based on inherency “ain’t necessarily so.” This standard for successfully arguing inherency has been around for a long time. Inherency must be certain. See, e.g., Ex parte McQueen, 123 USPQ 27 (Bd. App. 1958).

Celltrion also made a hard-to-follow argument that the common knowledge of a POSA  and the intrinsic evidence make clear that the “at least 98% limitation “defines a rate of aggregation over a particular time, under particular conditions.” The Fed. Cir. dismissed this argument as contradicting the plain claim language: “Nothing in the claims or the specification suggests that a “rare [of aggregation] must be calculated. Rather the claims states that after two months, the formulation is measured by SEC, and the result is either above 98%–within the scope of the claim—or below 98%–outside the scope of the claim.”

Celltrion’s obviousness argument was dismissed in one paragraph. The Fed. Cir. agreed with the district court: “[B]eginning with claim 5 of the ‘594 patent, [the POSA] would not have been motivated to achieve the 98% native conformation limitation and would not have had a reasonable expectation of achieving that level of conformation after two-months storage…[I]t suffices for us to  conclude that one claim difference—the stability limitation—renders claim 5 of the ‘594 patent patentably distinct  from the asserted claims of the ‘865 patent.” The panel did not discuss OTD in view of this difference. The opinion closes with some dicta about the presence or absence of glycosylated VEGF peptides that is, thankfully, beyond the scope of this post.

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