Tag Archives: prior art

Federal Circuit Affirms Patent Rejection for Lack of Enablement in In re Pen

by Dennis Crouch

The Federal Circuit (CAFC) recently affirmed a USPTO enablement rejection — holding that the patentee did not enable the “full scope” of the claimed invention.  In re Pen, 23-2282 (Fed. Cir. 2024) (non-precedential).  As an aside, the listed inventor’s legal name is “The Pen;” first and last name respectively, with no middle initial.  Based upon Pen’s address, he is related to “The People’s Email Network.”  In the case, Pen represented himself pro se.

Pen’s patent claimed “polycyclic metallole heteroatom rich conductive long chain polymers” comprised of certain repeating units. The idea here is to create a conductive polymer for use in new battery technology.  Key limitations in the claims at issue here are that the metallole heteroatom is nitrogen, there are more than eight repeating units (n>8), and a substituent R can be any substituent.

In affirming the PTO’s refusal, the Federal Circuit found that substantial evidence supported the Board’s factual findings on the Wands factors and found no legal error in its enablement analysis.

As the Supreme Court did in Amgen, the Federal Circuit focused on the breadth of the claims compared to the teachings of the specification and the along with the state of the prior art. The court noted that the claims allow R to be any substituent and also permitted any number of repeating units n to be over 8.

The state of the prior art also weighed against enablement, as the closest prior art polymers only had n=8 repeating units. The court rejected the appellant’s argument that this reasoning was illogical because it would require the invention to already exist in the prior art. Rather, the proper analysis looks at the gap between the scope of the claims and what the prior art already enables.  That gap must be filled by the specification.

Additionally, the court found that the field of conductive metallole polymers is unpredictable, further weighing against enablement. While the appellant argued that a skilled artisan could polymerize the monomers and carry out the claimed reactions based on the specification, the court emphasized that this does not necessarily enable the full scope of n values and R substituents covered by the claims.

Regarding the amount of guidance and examples in the specification, as well as the quantity of experimentation required, the court agreed with the Board that the specification did not provide sufficient guidance to enable the full claim scope without undue experimentation. Even if the specification enables some n values and R substituents, that is inadequate when the claims have open-ended ranges tat are much broader.

Throughout its opinion, the Federal Circuit stressed the breadth of the claims compared to the more limited disclosure. “The specification must enable the full scope of the invention as defined by the claims. . . . In short, the more you claim, the more you must explain.”  Citing Amgen Inc. v. Sanofi, 143 S. Ct. 1243 (2023).

The appellant made several arguments that the Federal Circuit rejected. First, the appellant argued that the choice of R substituent does not affect the conductivity or synthesis of the polymer.  The idea here is that comprising-style claims are always extremely broad in areas of less importance, and that reality should not spoil the validity of those patents.   Instead of fully engaging, the court noted this argument was made for the first time on appeal and was therefore forfeited.

Second, the appellant challenged the Board’s reliance on references not cited by the Examiner when discussing the closest prior art. The court disagreed that this constituted a new ground of rejection, finding the Board merely further explained the Examiner’s reasoning and the underlying legal standards.

Finally, the appellant argued that the Examiner’s analysis on some of the Wands factors was conclusory and irrelevant included boilerplate language, and that the Board had improperly relied upon that analysis. While the court agreed some of the Examiner’s language was “less than exemplary,” it found no reversible error in the Board’s ultimate conclusions on the Wands factors.

This case again includes strong language surrounding the enablement requirement.  However, the case arises in the “unpredictable arts” of chemistry that appears continue to be a key feature of enablement rejections that stick.

Navigating the USPTO’s Regulatory Wave: Key Comment Deadlines for Summer 2024

by Dennis Crouch

Over the past two months, the USPTO has issued an unusually large number of public comment requests related to various proposed rules and procedure changes. This wave of RFCs includes significant proposals aimed at adjusting patent fees for fiscal year 2025, refining terminal disclaimer practices, and addressing the impact of artificial intelligence on prior art and patentability. The agency is also seeking feedback on formalizing the Director Review process following Arthrex and various changes to IPR proceedings, including discretionary review. And there’s more… (more…)

Discerning Signal from Noise: Navigating the Flood of AI-Generated Prior Art

by Dennis Crouch

This article explores the impact of Generative AI on prior art and potential revisions to patent examination standards to address the rising tidal wave of AI-generated, often speculative, disclosures that could undermine the patent system’s integrity.


The core task of patent examination is identifying quality prior art.  References must be sufficiently accessible, clear, and enabling to serve as legitimate evidence of what was previously known.  Although documents are widely available today via our vast network of digital communications, there is also increasing junk in the system — documents making unsubstantiated claims that are effectively science fiction.  Patent offices prefer patent documents as prior art because they are drafted to meet the strict enablement standards and filed with sworn veracity statements. Issued patents take this a step further with their imprimatur of issuance via successful examination.  Many of us learned a mantra that “a prior art reference is only good for what it discloses” — but in our expanding world of deep fakes, intentional and otherwise, is face value still worth much?

In a new request for comments (RFC), the USPTO has asked the public to weigh in on these issues — particularly focusing on the impact of generative artificial intelligence (GenAI) on prior art. (more…)

The Use of Mandated Public Disclosures of Clinical Trials as Prior Art Against Study Sponsors

By Chris Holman

Salix Pharms., Ltd. v. Norwich Pharms. Inc., 2024 WL 1561195 (Fed. Cir. Apr. 11, 2024)

Human clinical trials play an essential role in the discovery, development, and regulatory approval of innovative drugs, and federal law mandates the public disclosure of these trials. Pharmaceutical innovators are voicing concern that these disclosures are increasingly being used as prior art to invalidate patents arising out of, or otherwise relating to, these trials, in a manner that threatens to disincentivize investment in pharmaceutical innovation. A recent Federal Circuit decision, Salix Pharms., Ltd. v. Norwich Pharms. Inc., illustrates the concern.  In Salix, a divided panel upheld a district court decision to invalidate pharmaceutical method of treatment claims for obviousness based on a clinical study protocol published on the ClinicalTrials.gov. website. The case garnered amicus curiae briefs filed by several innovative pharmaceutical companies in support of the patent owner, Salix Pharmaceuticals. (more…)

Overlapping Ranges in Claims and Prior Art Result in Invalidation of Patent on Transdermal Patch for Parkinson’s Disease

By Chris Holman

UCB, Inc. v. Actavis Lab’ys UT, Inc., 2023 WL 2904757, — 4th —   (Fed. Cir. Apr. 12, 2023)

Rotigotine is a drug used to treat Parkinson’s disease. People with Parkinson’s disease experience significant gastrointestinal dysfunction, such as difficulty swallowing, which can frustrate the oral administration of drugs. However, the complications associated with oral treatment can be avoided by means of a transdermal patch that delivers the drug through the patient’s skin.  In order to cross the skin barrier, however, the drug must be in an “amorphous,” i.e., non-crystalline, form.  If the drug crystallizes in the patch, it will generally not be able to cross the skin barrier.

In 2007, UCB invented and marketed “original Neupro,” a transdermal patch for the treatment of Parkinson’s disease containing a dispersion of amorphous rotigotine and polyvinylpyrrolidone (PVP), with the PVP functioning as a stabilizer. Unfortunately, soon after original Neupro entered the market it was found that the rotigotine was crystallizing when stored at room temperature, rendering the drug ineffective.  This caused UCB to recall the product from the U.S. market in April 2008 (although it remained in limited use under a compassionate-use program). In Europe, regulators allowed original Neupro to stay on the market, under the condition that it would only be marketed under “cold-chain conditions,” i.e., it would be stored in a refrigerator.

The patent at issue in this case, U.S. Patent No. 10,130,589, is directed towards UCB’s solution to this problem, which was to essentially double the amount of PVP in the patch, from original Neupro’s weight ratio of rotigotine to PVP of 9:2 to the new, reformulated Neupro’s weight ratio of 9:4. In particular the ‘589 patent claims a method for stabilizing rotigotine by combining a non-crystalline form of rotigotine with PVP to form a solid dispersion, wherein the weight ratio of rotigotine to PVP is in a range from about 9:4 to 9:6. UCB re-entered the U. S. market with its reformulated Neupro in 2012.

In 2019, UCB sued Actavis for infringing the ‘589 patent in a Hatch-Waxman lawsuit.  The district court found the asserted claims to be invalid based on anticipation and obviousness, particularly in view of earlier-issued UCB patents, i.e., the “Muller patents,” which disclosed combinations of rotigotine and PVP present at a range of weight ratios from 9:1.5 to 9.5. Note that the Muller patents cover both original Neupro (9:2) and reformulated Neupro (9:4), while the ‘589 patent (claiming a range of 9:4 to 9:6) only covers reformulated Neupro. Significantly, UCB had successfully asserted a Muller patent in a previous ANDA suit that resulted in an injunction preventing approval of Actavis’s ANDA until the relevant Muller patent’s expiration in March 2021. The ‘589 patent would not have expired until December 2030, and thus could have delayed FDA approval of a generic version of Neupro by nine additional years.

On appeal, the Federal Circuit reversed the district court’s anticipation ruling, but affirmed on the basis of obviousness. The opinion, authored by Judge Stoll, begins by explaining that Federal Circuit precedent sets forth an established framework for analyzing whether a prior art reference anticipates a claimed range. If the prior art discloses a point within the claimed range, the prior art anticipates the claim. On the other hand, if the prior art discloses an overlapping range, the prior art anticipates the claimed range “only if it describes the claimed range with sufficient specificity such that a reasonable factfinder could conclude there is no reasonable difference in how the inventions operate over the ranges.”

In the case at hand, the prior art Muller patents disclose a range (9:1.5 to 9.5) that overlaps with the range claimed in the ‘589 patent (9:4 to 9:6). The Federal Circuit found that the district court had erred by failing to analyze this as an overlapping range case, but to instead treat this as a case in which the prior art discloses a point within the claimed range.  The Muller patents did not literally disclose any point within the range claimed in the ‘589 patent, but the district court had nonetheless concluded, based on expert testimony, that the range disclosed in the Muller patents would implicitly teach a person of skill “a few examples” of specific weight ratios, including 9:4 and 9:5 weight ratios of rotigotine to PVP. Nonetheless, the district court’s error with regard to its anticipation analysis was rendered moot when the Federal Circuit proceeded to affirm its obviousness finding.

Judge Stoll cited Federal Circuit precedent for the proposition that there is a presumption of obviousness when a claimed range overlaps with a range disclosed in the prior art. Although this presumption can be overcome if, e.g., the prior art teaches away from the claimed range, or the claimed range produces new and unexpected results, or other evidence demonstrates the nonobviousness of the claimed range, in this case the Federal Circuit agreed with the district court that UCB had failed to present evidence to rebut the presumption of obviousness.

For example, the district court had not erred in its decision to disregard the commercial success of reformulated Neupro, based on a lack of a nexus between the drug’s commercial success and the claimed invention. In particular, the Federal Circuit agreed that the existence of the Muller patents weakened UCB’s evidence of commercial success, because these patents operated as blocking patents, dissuading competitors from developing a rotigotine transdermal patch, at least until the Muller patents expired. While rejecting UCB’s suggestion that the court’s analysis had branded all co-owned patents as “blocking” patents, the court noted that in this case UCB had held exclusive worldwide rights to rotigotine for all therapeutic indications since 1998, and that until the Muller patents expired Actavis had been enjoined from marketing a generic version of reformulated Neupro.

Guest Post by Profs. Masur & Ouellette: Public Use Without the Public Using

Guest post by Professors Jonathan S. Masur (Chicago Law) and Lisa Larrimore Ouellette (Stanford Law).

What is it that makes a use “public” for purposes of the public use bar? Does it matter whether the person doing the using is a member of the public, as opposed to the inventor? Or does it matter whether the use is itself in public, as opposed to taking place in secret behind closed doors? As it turns out, the answer to both questions is “yes,” but the questions are not as distinct from one another as that formulation might make it seem. Instead, the issue of who is doing the using turns out to affect where and how that use must occur if it is to be public use.

Begin with the question of who is doing the using. Most cases of “public use” have involved use by at least one member of the public—“a person other than the inventor who is under no limitation, restriction or obligation of secrecy to the inventor.” And when an invention is in use by a member of the public (rather than the inventor), it is blackletter law that the use can be “public use” even if it takes place entirely in secret, behind closed doors. In addition, it is also blackletter law that the use need not enable the invention to constitute prior art. No member of the public needs to see all the details of the invention or be able to reproduce it—it is enough that at least one person has come to rely on the availability of the invention free from any patent-based restriction.

But as we explain in a forthcoming article, a small line of cases suggests there is a second route to public use: even if no member of the public uses the invention, an invention can be placed in public use if it is used by the inventor, but only if it is displayed to the public in such a way that the relevant public could have understood the invention. That is, there can be public use without the public using, but only if that use is out in the open and with something like an enablement requirement. See Real-World Prior Art, 76 Stan. L. Rev. (forthcoming 2024). These cases appear to rely on an idea of constructive public knowledge: just as a conference poster can be invalidating printed publication prior art if a researcher could have learned about the invention by reading it, an inventor’s demonstration of an invention can be an invalidating public use if someone could have learned about the invention from observing the demonstration. Likewise, the Federal Circuit has held that display of an invention is not public use “if members of the public are not informed of, and cannot readily discern, the claimed features of the invention.” The only exception to these rules has come when the inventor is engaged in secret commercial use of the invention. Some courts have held that this puts the invention into public use. But more recently, the Federal Circuit has instead begun to hold that this places the invention on sale, because the whole point of the use is to exploit the invention commercially. We agree with the Federal Circuit panels that have held that the on sale bar is a better fit in these situations.

The upshot from these two lines of precedent is that the question of whether an invention is in public use depends intimately on who is doing the using. If the user is someone other than the inventor, then there is public use (a) even if the use is taking place in secret, and (b) irrespective of whether the user can figure out how the invention works (enablement). But if the inventor herself is the one doing the using, then (a) the use must be taking place in public, and (b) the use must be enabling.

As one might predict, the grouping of these two approaches under the single heading of “public use” has led to confusion among litigants and, in some cases, courts. Two new Federal Circuit decisions this month add to this “public use without the public using” line of cases and demonstrate the pitfalls of failing to keep the interlocking public use rules straight. In Minerva v. Hologic, the court held that display and demonstration of a medical device at a gynecological trade show constituted public use. The patentee, perhaps misunderstanding this line of doctrine, argued that it could not be public use because no member of the public used the invention. But the court held that “public use may also occur where, as here, the inventor used the device such that at least one member of the public without any secrecy obligations understood the invention.” Similarly, In re Wingen held that display of an inventive “Cherry Star” flowering plant at a private Home Depot event placed the plant into public use. The patentee argued that the display did not disclose the claimed genetics of the plant—which could have been a successful argument given the enablement-like inquiry imposed on other similar cases—but the court held that this argument was forfeited because it was not raised in proceedings below. It seems likely that the lawyers who argued the case before the PTAB had not thought to make this argument because they did not realize that use by the inventor requires enablement. Our article includes numerous examples of district courts that were similarly confused by the rules that vary depending on who’s doing the using.

As we explain in our article, treating enabling demonstrations by the inventor as prior art makes sense as a matter of patent policy. But lumping these cases under the “public use” umbrella has created confusion and mistakes among the lower courts. Going forward, we think the Federal Circuit should be explicit that there are two distinct routes to public use: (1) use by a member of the public—someone under no obligation of confidentiality to the inventor—which can take place in secret and need not be enabling, and (2) use by the inventor, which must take place in public and enable the invention.

Alternatively, and perhaps even better, the Federal Circuit could decide that the inventor-use category of activities instead implicates the “otherwise available to the public” prong of § 102. An enabling demonstration, where the public learns about the invention but cannot use it, could be the paradigmatic example of an activity that makes an invention available to the public without creating any other type of prior art. This is not a full solution given all the pre-AIA patents still in force, and in light of the strong policy reasons for barring pre-AIA patents that were displayed publicly we can see why courts have tried to fit these cases within the “public use” category. Regardless, for patentees and their attorneys, Minerva v. Hologic and In re Wingen serve as a reminder to avoid disclosing the details of an invention before they are ready to file a patent application—and if a disclosure does occur, they should remember to preserve the argument that it wasn’t actually enabling!

Public use == “accessible to the public.”

by Dennis Crouch

Bottom line in this new Minerva case — file your patent application before bringing a new product to a trade show. 

The Old Case: The battle between Hologic and Minerva went to the US Supreme Court in 2021; with the Court retained the doctrine of assignor-estoppel that bars a patent assignor from later challenging the patent’s validity or enforceability. Minerva Surgical, Inc. v. Hologic, Inc., 141 S. Ct. 2298 (2021). Although the doctrine remains, the Court narrowed its scope to only apply , but narrowed its scope to cover only situations where assurances (implied or express) made at assignment are later being undermined.  Thus, when claims are materially broadened post-assignment, the assignor should probably be permitted to challenge those claims.  As is true in many inter-corporate battles, the legal claims are being fought along different lines in various tribunals and cases.  This week, the Federal Circuit issued a new decision — this time involving upstart Minerva as the plaintiff suing Hologic for infringing its U.S. Patent No. 9,186,208.

Minerva’s ‘208 patent claims a device for endometrial ablation  and includes a 2011 priority filing date.  As you can see from the diagram above, the device includes both inner and outer frame elements, and the claims require that these “have substantially dissimilar material properties.”  This allows portions of the device to retain more flexibility (those coming in contact with the uterine lining) with other portions having more strength/durability.  Still, the whole head needs to be collapsible as well.

The application was filed in 2011, but back in 2009 Minerva had been doing testing on a prototype “Aurora device” that included inner/outer frames made of two different types of steel.  The devices were brought to a trade show (AAGL 2009) and Minerva gave a presentation on the device and distributed a brochure. It was also pitched to a potential acquirer.

In the appeal, Minerva provided three arguments as to why this activity was not an invalidating public use:

  1. Displaying the device at a trade show table does not count as a “use”
  2. Although the displayed device used two different types of steel, they were not different enough to satisfy the claim requirement of having “substantially dissimilar material properties.”
  3. The invention was not yet “ready for patenting” and therefore its public use was not disqualifying.

The Federal Circuit rejected each of these arguments in-turn.

Public Accessibility equals Public Use: Although the statutory language of “public use” suggests that the bar is triggered only if the invention is actually used.  The Federal Circuit explained here hat its interpretation is more expansive, and includes situations where the patentee made the invention “accessible to the public.” See, Delano Farms Co. v. California Table Grape Comm’n, 778 F.3d 1243 (Fed. Cir. 2015).  Here, the Aurora device was made available to attendees at a major trade show spanning several days.  Minerva brought 15 fully-functional devices and internally reported “lots of interest” and that the table was “busy.”

In Motionless Keyboard Co. v. Microsoft Corp., 486 F.3d 1376 (Fed. Cir. 2007), the Federal Circuit seemed to have ruled that public use requires use. Although publicly shown, the claimed keyboard was deemed not in public use since it was “visually displayed … without puting it into use [and] was never connected to be used in the normal course of business to enter data into a system.” Id.  Here in Minerva, Judge Reyna distinguished Motionless Keyboard, noting that Minerva’s disclosures were “well beyond” what was seen in that prior case.  The court focused on the sophistication level of the trade show attendees and their ability to closely scrutinize the device and see how it operated.

The inescapable conclusion … is that Minerva allowed knowledgeable individuals to scrutinize the invention enough to recognize and understand the SDMP technology Minerva later sought to patent.

Slip Op.  On appeal, Minerva argued that its prototype’s inner/outer frames did not have substantially different material properties.  On appeal, the federal Circuit also rejected that argument since Minerva materials from that time touted the benefits of the device’s SDMP.

Ready for Patenting: Public use only creates a bar to patenting if the invention was “ready for patenting.” Here, the court concluded that it was ready for patenting since (1) it had been reduced to practice; and (2) Minerva had sufficient documentation prepared describing the invention.

At the time, Minerva was still working to improve the technology and it had not yet been used to actually perform ablation on a living human.  On appeal, the Federal Circuit noted that no evidence (beyond common sense) indicates that the device’s only use is on live human tissue.  The court also noted that Minerva had conducted lab studies sufficient to move-on for clinical trials on humans.  Minerva’s final product used slightly different materials, but the court concluded that Aurora was still itself ready for patenting. “later refinements” and “fine tuning” go beyond reduction to practice and do not negate a public use.