A Blog About Intellectual Property Litigation and the District of Delaware


If we keep using this image, people are going to think that all of Wilmington is on the water. Imagine their surprise when they arrive!
If we keep using this image, people are going to think that all of Wilmington is on the water. Imagine their surprise when they arrive! Andrew Russell, CC BY 2.0

This week, the D. Del. website posted an opening for a term law clerk with Magistrate Judge Hatcher.

As most of our readers probably know, there are two types of judicial clerks: permanent and term. A permanent clerk is, well, permanent. They stay indefinitely. A term clerk stays for, typically, a one-year term, most often starting in September.

Serving as a term clerk is an amazing opportunity for an attorney and I highly recommend it. It gives you an incredible perspective on how the Court works, how judges manage …

Many motions are longshots. Thrown out like a message in the bottle, with little hope that they will ever find a helpful shore. An act born of desperation more than reason.

AI-Generated, displayed with permission

Damages Daubert's are the exception. If you can cobble together a good one, you've got a fair chance of knocking out a big portion of the damages case.

This is exactly what happened last week in Fundamental Innovation Systems Int'l LLC v. Anker Innovations Ltd., C.A. No. 21-339-RGA (D. Del Feb. 11, 2025). The plaintiff there based its damages theories on a series of other licenses that included the patents in suit along with more than 200 other US and foreign patents.

The …

Parade of Horribles.jpg
The Looming Parade of Horribles, AI-Generated, displayed with permission

I’m partial to percussion and noticed that there was a gaping hole of staccato in the rising swell of the IPDE music videos, subtle though it may have been in the background of Andrew's singing and Nate’s interpretive dance performances. Leaving the snare drum at home, today I chime in only with the lonely voice of a wistful triangle to supplement this week’s stories with a tale from a faraway land—the Eastern District of Texas.

Why do we in Delaware care about this opinion? It gave me a fresh appreciation for the orderly composition of Delaware scheduling orders. It involved a problem that cannot arise in a District of Delaware …

Inventorship is either the most or least important aspect of a patent, depending on who you ask. For my purposes as a lawyer (and likely yours as a reader), the inventor of a patent rarely has any impact on the substantive issues especially because 35 U.S. Code § 256 allows for correction and specifically states:

The error of omitting inventors or naming persons who are not inventors shall not invalidate the patent in which such error occurred if it can be corrected as provided in this section.

Be it Kodos or Kang, the name on the front usually has only marginal relevance to my work.

Presumably it's a big deal to the scientist.

AI-Generated, displayed with permission

One of the few areas where the issue can come up is inequitable conduct. This was the case in Equil IP Holdings LLC v. Akamai Technologies, Inc., C.A. No. 22-677-RGA, D.I. 192 (D. Del. Feb. 14, 2025).

The patent asserted in that case shared a specification with an earlier patent, but originally had no inventors in common. When the plaintiff brought an IPR asserting that the earlier patent anticipated the later, the patentee filed the necessary paperwork to add a common inventor to the earlier patent and thus remove it from the world of prior art as it was no longer an invention "by another." The defendant alleged that this change in inventorship was fraudulent and constituted inequitable conduct, and moved to amend its answer to assert the defense.

Plaintiff opposed on the grounds of futility, arguing that—post Therasense—incorrect inventorship cannot ...

Fish Traps
Chris J Walker, Unsplash

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 hope some of you saw the musical video Andrew posted yesterday before it was taken down in a copyright strike by the Prince Estate due to his eerily pitch perfect parody. The costumes alone were worth the price of admission.

Honestly the photo doesn't do it justice
Honestly the photo doesn't do it justice AI-Generated, displayed with permission

Hopefully tomorrow's video -- Injunction Junction -- fairs better.

Mallinkrodt Pharms. Ireland Ltd. v. Airgas Therapeutics LLC, C.A. No. 22-1648-RGA (D. Del. Feb 12, 2025). presented an interesting twist on the tried and true preliminary injunction formula.

The likelihood of success analysis was pretty standard (although it touched on one of my favorite issues -- drug interaction). Ditto for irreparable harm, with the Court …

Proof I have other hobbies
Andrew E. Russell, displayed with permission

I don't talk about it much on the blog, but my other hobby (beyond writing about litigation and the District of Delaware for funsies, photography, and having an absurd-by-today's-standards number of children) is writing and speaking about AI and the law. I've been speaking about AI issues on panels at conferences since 2018. Most recently, I moderated a Sedona Conference panel about Copyright and AI.

In the context of copyright and AI, the question of whether training an AI model on copyrighted content is fair use is basically life-or-death for a lot of current AI models. Big generative models like ChatGPT are (typically) trained on giant masses of data collected from books, …

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 blog
This is perhaps my favorite picture I've used on the blog AI-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.

Judge Burke ...

We'll all get it right eventually
Simon Ray, Unsplash

We've posted twice recently on Magistrate Judge Tennyson's practices regarding how long the parties should meet-and-confer before bringing a discovery dispute. In the prior posts, the parties presented a single discovery dispute issue. The parties initially met-and-conferred for 12 minutes, and the Court sent them back to meet-and-confer further. The Court later OK'd the dispute after they spent a total of 31 minutes on the issue.

On Friday, the Court issued an order in another case giving some more insight into this meet-and-confer requirement. In Media Content Protection LLC v. Dell Technologies, Inc., C.A. No. 20-1240-CFC-EGT (D. Del.), the parties filed a motion to raise three discovery issues with the Court, including two …

Zig Zag
Jack Finnigan, Unsplash

Contention interrogatory responses are a frequent topic of dispute. In theory, using damages as an example, the way it works is this:

  1. Defendant, who does not have the burden, sends a contention interrogatory.
  2. Plaintiff provides contentions.
  3. Defendant takes discovery based on the contentions.
  4. Plaintiff provides expert reports that fairly elaborate on the contentions.
  5. Defendant responds using the discovery it took based on the contentions.
  6. Plaintiff offers expert testimony at trial that is a fair elaboration on their reports.
  7. Defendant moves to strike any testimony that goes beyond the reports.

The process can get hung up on step 2, however, because parties may try to short-circuit the process and avoid giving away or getting nailed down on …