Estoppel is a word rarely used by the layman. It is a hothouse flower that seems able to grow only in the rarefied loam of the law, dying quickly when exposed to modern vernacular. \
But it was not always so. Like much legal jargon, it springs from old French, and in particular "estopail" which meant the plug you put in a barrels bunghole to prevent your wine from leaking out.
Today's opinion in Cognipower LLC v. Fantasia Trading LLC, C.A. No. 19-2293-JLH-SRF (D. Del.) dealt with a rather novel estoppel argument I hadn't seen before. The Defendant had filed multiple IPRs on the many asserted …
A very blurry picture of a claim from one of the asserted patents, highlighting roughly the text that the patentee seemed to seek summary judgment on.RE47,031
It's common for parties to not dispute the presence of some portions of a patent claim in an accused product. For example, in a patent for a "computing device" with software meeting certain limitations, the defendant may not dispute that the presence of a "computing device"—but might vigorously dispute that the software it runs meets the remaining claim limitations.
In most patent cases, the presence of at least some portion of the claim limitations in the accused product is not disputed—and often, quite a few limitations are not disputed. But the parties regularly …
Long ago when I was interviewing for law jobs, my go-to move when the interview was devolving into the inane pitter patter meant to suss out if the applicant (me) was a secret axe-murderer or fifth columnist, was to ask if they were working on a book.
The joke at the time was that within the desiccated husk of every lawyer there is a creative who yearns for an outlet. In the fullness of time, I have come to see that it may also reflect the fact that a lawyer will write a book-length treatise about absolutely anything.
This leads me to another in my serious of rarely cited rules, and the case of HQ Specialty Pharma Corp. v. Fresenius Kabi USA, LLC, C.A. No. 21-1714-MN, D.I. 325 (D. Del. July 31, 2025). Following a jury trial and the resolution of post-trial motions, Judge Noreika ordered the parties to submit a form final judgment. The parties jointly submitted an agreed upon form that was about 7 pages long and contained numerous whereas clauses referencing the jury trial and a series of recitals on the form of an injunction pending appeal.
Despite the parties agreeing on the judgment, Judge Noreika rejected the submission citing to a portion of Rule 54 that oft goes unnoticed:
Having reviewed the proposed Final Judgment, the parties' proposal is REJECTED. The proposed judgment does not comply with Rule 54 of the Federal Rules of Civil Procedure, which specifies that "[a] judgment should not include recitals of pleadings, a master's report, or a record of prior proceedings." The parties may stipulate separately to an order that includes their agreed-upon terms, but the judgment must conform with Rule 54.
Id.
The parties did, in fact, resubmit that judgment re-captioned as a stipulation, which the Court promptly so-ordered. They then submitted a much shorter (about a page in total) final judgment that omitted the recitals and just noted how the various claims had been resolved, which was entered the next day.
A patent figure. It has an indisputable date, a specific technical diagram, and a description. How much clearer can you get?U.S. Pat. No. 777,777 ("Hat-Clasp")
On Friday, Judge Williams resolved a case narrowing dispute in Nexus Pharmaceuticals, Inc. v. Execla Pharma Sciences, LLC, C.A. No. 22-1233-GBW (D. Del.).
The parties disputed the numerical limits for case narrowing. The Court adopted a proposed limit of 4 obviousness combinations per claim, with no more than eight combinations total, and 10 total prior art references. The patentee offered to narrow to 7 asserted claims.
The Court noted that the order was consistent with its precedent, in which it allowed no more than 10 claims, 10 prior art references, and 20 prior art arguments.
The Court also addressed what counts as a "reference." The patentee tried to limit the accused infringer so that every document counts as its own reference, even if the asserted obviousness combination is a prior art device, product, or system itself rather than the documents that describe that system.
"Just imagine this page holds one of the in-depth and fulsome post-grant review petitions we're totally going to file on these patents"Kelly Sikkema, Unsplash
I know some readers probably want an update on the protective order hearing. I expect that will be a hefty post of interest to all D. Del. litigants—but I need to get the transcript first. In the mean time, though, please enjoy this spare and jargon-filled post which is only going to be of interest to patent practitioners.
We've talked about pre-institutionstaysbefore, and how hard they are to achieve. What's even harder? A stay of patent litigation before a patent challenge has even been filed.
Plaintiff's principal with his towering pillar of hatsAI-Generated, displayed with permission
If you happen to be in Wilmington, DE tomorrow—perhaps as a summer associate—and feel like attending an interesting hearing, it could be worth stopping by Judge Noreika's Courtroom 4A at 10am.
The hearing involves an alleged protective order violation by plaintiff Rein Tech and its principal. See Rein Tech, Inc. v. Mueller Systems, LLC, C.A. No. 18-1683-MN, D.I. 170 (D. Del. May 16, 2025).
An Alleged Disclosure of AEO Information And an Alleged Prosecution Bar Violation
Rein Tech's principal apparently wears many hats. In addition to being the head of Rein Tech, he is also the named inventor on the asserted patents, the prosecuting attorney …
Wow. In Belvac Production Machinery, Inc. v. Adonis Acquisition Holdings, LLC, C.A. No. 25-166-JLH (D. Del.), the plaintiff moved to compel the defendant to preserve all random access memory ("RAM") copies of certain copyrighted software that is apparently used to operate equipment.
To me, this is a wild motion—although it takes a bit of knowledge about computer memory to show why.
Some Background on Computer Memory
Unlike Nate, who wisely avoided expounding on analytical chemistry, I feel like some background on how computer memory works is needed here, to help understand just what plaintiff is asking for. The parties didn't include this in their briefing—but they probably should have explained things a bit …
I fancy myself a bit of an aficionado of the local rules (a petty fiefdom, I know, but I rule it fairly). Like any Delaware lawyer I can rattle off the big ones—7.1.1, 16.4., 26.2 and the like—and I can even pull some b-sides out in a pinch.
But I must say I had to have a real think when I read Judge Bataillon's recent order in Astellas Pharma Inc. v. Ascent Pharms., Inc., C.A. No. 23-486-JFB-EGT (D. Del. July 28, 2025) and saw a citation to D. Del. LR 5.4(b)(3).
Obviously you'll all have this one memorized, but just in case any lay readers are …
I couldn't find a real image of a border that is "porous to the extent that it is decipherable"AI-Generated, displayed with permission
Even 10+ years after Alice, the standard for invalidity under § 101 feels inconsistent, and there is a lot of room for any two human beings (judges or otherwise) to look at the same patent and have different views. This is particularly true when you factor in the procedural hurdles, which ultimately give the Court a range of options on when to deal with a § 101 motion (e.g., before summary judgment, at summary judgment, or at trial/post trial).
So, when a D. Del. judge issues a § 101 decision, I often think it often …
An embodiment of the lens at issue—yes, this is a single claim "element"U.S. Pat. No. 6,844,990
Judge Burke issued a fascinating invalidity decision yesterday in Immervision, Inc. v. Apple, Inc., C.A. No. 21-1484-MN-CJB (D. Del.). It addresses an invalidity issue I had honestly never seen litigated—a "'single means' claim"—and, along the way, it addresses what a claim "element" is and when the "clear and convincing" standard applies to invalidity.
Basically, the whole thing is a page-turner for someone who deals with these issues, and well worth reading. I'll outline some of the most interesting points below.
"Single Means" Invalidity Is a Thing
The invention at issue is an optical lens. The opinion involves an independent claim …
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