We first posted a reminder that reverse DOE and ensnarement exist back in 2021, and then again in 2023. But here, now, in 2025, we just got some nice guidance from the Court about ensnarement, and it seems like a great time to put out another reminder.
What Are They?
The Reverse Doctrine of Equivalents deals with a situation where the accused product literally reads on the claims, but is not actually doing what the patent is meant to cover. As we noted last time:
The [reverse doctrine of equivalents] rescues from infringement devices that literally satisfy the elements of a claim but perform the same function of the invention in a …
I am pleased to announce that, starting with Andrew's next post, we will be pivoting to a new format. No longer will we be analyzing the developments in IP law with mere written words. Instead, we will be creating Schoolhouse Rock style musical videos. Andrew's surprisingly moving singing voice will be accompanied by my own interpretive dance—leading you through the intricacies of the days' cases like a bee describing the way to honey.
This is perhaps my favorite picture I've used on the blogAI-Generated, displayed with permission
The subject of today's post, CosmoKey Solutions GmbH & Co. KG v. Duo Security, Inc., C.A. No. 18-1477-CFC-CJB, D.I. 413 (D. Del. Feb. 7, 2025) will also be the subject of our first song, "Sanction Sanctuary."
The title comes from the plaintiff's motion for sanctions -- unusual in the district outside of the Pennypack context. The issue there was that the defendant had produced almost all of its documents after the substantial completion deadline, resulting in extra work for the plaintiff, who sought fees as compensation. The defendant argued that the late production was not sanctionable because it was caused in large part by an error in their document collection that had initially missed all documents before 2018.
When people say that D. Del. is "against litigation funding," they imply that the Court has some kind of general bias against parties who use litigation funding. That's wrong. I've never seen a Delaware judge dislike or rule against a party because the party used litigation funding. And the Court as a whole is certainly not biased against plaintiffs (or defendants), funding or no funding.
With all of that said, I thought it was worth noting that Judge Burke recently ordered production of litigation funding material to the extent it related to the value of the patents.
After reviewing litigation-funding-related documents in camera, he ordered production of those that relate to the value of …
Old timers remember RainDance Techs., Inc. v. 10X Genomics, Inc., Civil Action No. 15-152-RGA, 2016 U.S. Dist. LEXIS 33875 (D. Del. Mar. 4, 2016). After the appendix of forms was banished from the Federal Rules of Civil Procedure, Judge Andrews' opinion in Raindance was among the first in the nation to hold that complaints alleging infringement had to do more than simply list the patent and the product as in the old Form 18.
For a couple years it was the citation of choice in the district for motions to dismiss, with every defendant arguing that the complaint lacked sufficient detail relating their product to the asserted patent claims.
Judge Burke issued an interesting claim construction opinion on Thursday of last week, invalidating a claim where one of two ways to infringe was scientifically impossible.
One claim limitation was set forth in the alternative:
A communications apparatus for transmitting electric or electromagnetic signals over air
Satius Holding, Inc. v. Samsung Electronics Co., Ltd., C.A. No. 18-850-CJB (D. Del. Dec. 12, 2024).
The parties agreed the it is "scientifically possible" to transmit "electromagnetic signals" over air, but the defendant argued that it was impossible to transmit "electric" signals over the air:
Defendants assert that one of those two options—“transmitting electric . . . signals over air”—amounts …
"Behold, our fulsome and complete damages theory disclosure. I'm sure this won't cause us any problems down the line."Andy Bridge, Unsplash
Parties in patent cases are often tempted to provide bare-bones responses to contention interrogatories, offering just enough to preserve their ability to expand on the arguments later during expert reports. That's easier, obviously, than providing more detailed contentions, and it also maintains flexibility as discovery develops.
Plus, parties simply may not have fully developed their theories at the time contention interrogatories are due. Expert reports are when theories are typically fully fleshed out, after discovery has closed and the universe of information is set, more or less.
But there is another consideration as well, beyond preventing a …
We lawyers move things around all the time. Some due date or another falls on a vacation, an expert gets sick, a bunch of files won't load -- a thousand different minor catastrophes can occur. In Delaware, the result is almost invariably a stipulation to move the relevant dates.
WHEREAS, on the first day the waters turned to blood;AI-Generated, displayed with permission
Typically for little interim deadlines, the Court will grant the stipulation as a matter of course. Deadlines a little closer to trial are a bit trickier. Judge Connolly, for instance, notes in his form scheduling order that "Should the parties later stipulate or otherwise request to have the [SJ and Daubert] reply brief deadline extended, the parties …
Judge Burke's decision in CosmoKey Solutions GmbH & Co. KG v. Duo Security, Inc., C.A. No. 18-1477-JLH-CJB (D. Del. Nov. 15, 2024) (Oral Order), deals with a stipulation that encompassed more than intended.
The case began life under the watchful gaze of Chief Judge Connolly. Like all patent cases assigned to him at the time, the scheduling order …
If law has one guiding principle, it is that words matter. The precise choice of verb or adjective can be the difference between friend and foe, peace and war, victory and defeat.
You've read Faust, you get it.
History's most famous lawyer?AI-Generated, displayed with permission
We saw a great example of this principle this week in I-Mab Biopharma, v. Inhibrx, Inc., C.A. No. 22-276-CJB (D. Del. Oct. 17, 2024) (Mem. Order). I-Mab was prought under the DTSA which allows damages to be calculated as either (1) damages for actual loss plus unjust enrichment or (2) a reasonable royalty. 18 U.S.C. § 1836(b)(3)(B).
The defendants—who unsurprisingly preferred a lower damages figure—served an expert damages report that noted that plaintiff's "actual damages" might be "zero." The plaintiff moved to exclude the opinion under Daubert, arguing that their damages theory was based on a reasonable royalty, and thus an opinion that their "actual damages" might be zero was neither here nor there, and was unduly prejudicial.
The defendant countered that the expert had meant that "Dr. Manning is 'not offering an opinion on actual losses, but instead references ‘actual damages’ as reflective of damages I-Mab may be awarded'—in other words, according to Defendants, the zero damages opinion is an opinion that Plaintiff’s reasonable royalty damages may be zero." Id. at 8 (quoting D.I. 364 at 23).
Judge Burke, however, found the expert's choice of words dispositive, and struck the so-called "zero damages opinion"
The Court agrees with Plaintiff that Defendants are ignoring the “actual words” that Dr. Manning used, as he did not opine in the zero damages opinion that Plaintiff’s “reasonable royalty damages” are zero (nor do Defendants point to anywhere else in Dr. Manning’s report where he opined that Plaintiff’s reasonable royalty damages should be zero). Nor do Defendants explain why an opinion that Plaintiff’s “actual damages . . . are zero” should be interpreted to actually mean that Plaintiff’s “reasonable royalty damages are zero.” Moreover, the Court agrees with Plaintiff that Dr. Manning does not seem to provide any facts or analysis in support of the zero damages opinion. Thus, Defendants have not sufficiently explained how, inter alia, Dr. Manning’s zero damages opinion is relevant in light of Plaintiff’s argument to the contrary; therefore it must be excluded.
Long answer - also yes, also obviously, but the timing is important.
AI-Generated, displayed with permission
The issue came to the fore in I-Mab Biopharma v. Inhibrx, Inc., C.A. No. 22-276-CJB (D. Del. Sept. 19, 2024) (Mem. Ord.). I-mAB is a DTSA action alleging the theft of about a dozen separate trade secrets. A few months back, the plaintiff went through a restructuring that resulted in several related entities now owning some or all of the trade secrets. The plaintiff then moved to add these entities as co-plaintiffs. Judge Burke denied the motion due to the potential for delay, given that the case was scheduled for trial int he near future.
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